Laytime Calculation in Ship Chartering: Complete Practical Guide to Laydays, Notice of Readiness, Demurrage and Time Sheets

Laytime calculation is one of the most important commercial skills in voyage chartering. Freight may be the headline number in a fixture, but the final financial result often depends on how correctly the parties count the time used for loading and discharging. A ship may earn a profitable freight rate and still lose a substantial part of the voyage result if the laytime provisions are misunderstood, if the Notice of Readiness is defective, if weather exceptions are applied incorrectly, or if the Statement of Facts is not checked carefully before a time sheet is prepared.

In a voyage charter, the shipowner undertakes to carry an agreed cargo from one place to another, while the charterer undertakes to provide the cargo, load it, discharge it, and pay freight in accordance with the charterparty. Laytime is the agreed period allowed to the charterer for cargo operations without additional delay payment. Once that agreed time has been exhausted, the ship is normally on demurrage, unless the charterparty provides otherwise. If the charterer completes cargo operations faster than the allowed time, the charterer may be entitled to despatch money if the contract contains a despatch provision.

Laytime is not merely an accounting exercise. It affects voyage estimates, freight negotiations, port selection, cargo scheduling, documentary practice, charterparty drafting, and post-fixture claims. A shipbroker who understands laytime can compare two apparently similar cargoes more accurately. A shipowner who understands laytime can price waiting risk more realistically. A charterer who understands laytime can avoid unnecessary demurrage and protect legitimate despatch. A port agent who understands laytime can prepare a Statement of Facts that reflects the real chronology of the port call.

The phrase laytime calculation in ship chartering covers several connected questions. When did the ship become an arrived ship? Was a valid Notice of Readiness tendered? Did notice time have to expire before laytime commenced? Was the charter a port charter or a berth charter? Did weather, holidays, strikes, shifting, congestion, or hold failure interrupt laytime? Was the laytime reversible, non-reversible, or averageable? Did the ship go on demurrage? Did time on demurrage run continuously? Did the charterparty require demurrage and despatch to be calculated on all time saved, working time saved, or another basis?

The purpose of this article is to provide a complete, practical, and professional guide to laytime calculation. It explains the main terminology, the legal and commercial logic behind laytime, the documents used in calculation, the role of BIMCO definitions and standard forms, and the way calculations are normally prepared from a Statement of Facts and a time sheet. It also gives detailed examples for dry bulk and tanker trades, because the practical application of laytime often differs between cargo sectors even though the basic principles are similar.

1. Meaning of Laytime in Voyage Chartering

Laytime is the amount of time contractually allowed to the charterer for loading and discharging the cargo. The parties may express laytime in several ways. It may be stated as a fixed number of days, such as five weather working days for loading and five weather working days for discharging. It may be stated as a rate, such as 8,000 metric tons per weather working day at load port and 6,000 metric tons per weather working day at discharge port. It may be stated as a total period for both operations, or as separate periods for each port.

The core commercial idea is simple. The shipowner has priced the voyage on the basis that the ship will spend a certain amount of time under cargo operations. The charterer is given that amount of time as part of the freight bargain. If the charterer uses more time than allowed, the shipowner receives compensation in the form of demurrage. If the charterer uses less time and the charterparty provides for despatch, the shipowner pays the charterer a reward for saving the ship’s time.

Laytime is different from the voyage itself. The voyage includes the preliminary voyage to the load port, the loading operation, the sea passage, the discharge operation, and any contractual obligations connected with completion of the voyage. Laytime concerns the specific portion of time allowed for loading and discharging. The fact that a ship is waiting at port does not always mean laytime is running. Conversely, once the ship is on demurrage, time may continue to count even during periods that would previously have been excepted from laytime, unless the charterparty clearly says otherwise.

A laytime clause is therefore a risk allocation clause. It decides how the cost of port delay is divided between the shipowner and the charterer. The more precisely the clause is drafted, the less room there is for later argument. The more casual the wording, the more likely it is that the parties will disagree about commencement, interruptions, demurrage, despatch, and supporting evidence.

2. Laytime, Laydays and Laycan Are Not the Same

One of the most common mistakes in chartering language is to treat laytime, laydays and laycan as if they are identical. They are related, but they do not mean the same thing. Laytime is the time allowed for cargo operations. Laydays are the dates during which the ship is expected or permitted to present for loading. Laycan is the laydays and cancelling period, meaning the contractual window within which the ship must be ready and after which the charterer may have a right to cancel if the ship is late.

In everyday market language, brokers often say that a cargo has a laycan of 10/20 July, meaning that the ship must be ready to load within that period and that the cancelling date is 20 July. The precise legal consequence depends on the charterparty wording. Some clauses require the shipowner to proceed with reasonable despatch toward the load port. Some give the charterer a cancellation option if the ship is not ready by the cancelling date. Some include an extension mechanism or a duty to declare whether the charterer will cancel once the shipowner gives notice of expected delay.

Laytime usually cannot commence before the first day of the laydays unless the charterparty permits earlier commencement or the charterer agrees to use the ship earlier. A ship may arrive before the first layday and tender a Notice of Readiness, but the question whether the notice is effective and when time begins depends on the charterparty. Modern standard forms often contain specific provisions governing early arrival, early NOR, and commencement of laytime if cargo operations begin before the laydays open.

The commercial difference matters. Laycan protects the charterer against late arrival. Laytime measures the cargo operation period after the ship is ready and a valid notice has been given. Demurrage compensates the shipowner if laytime is exceeded. Despatch rewards the charterer where time is saved and despatch is agreed. A clear laytime calculation starts by separating these concepts before any arithmetic is attempted.

3. The Basic Formula for Laytime Calculation

At its simplest, laytime calculation follows a logical sequence. First, identify the laytime allowed under the charterparty. Second, identify the moment when laytime began. Third, count all periods that count as laytime. Fourth, exclude periods that the charterparty excludes. Fifth, stop counting when loading or discharging is completed. Sixth, compare the time used with the time allowed. The result will show whether the charterer has time saved, time used exactly, or time on demurrage.

The calculation becomes complicated because each stage depends on contract wording and facts. A weather interruption may stop laytime under one clause but not under another. A holiday may be excluded under SHEX wording but included under SHINC wording. A strike may interrupt time if it is expressly excepted, but may not help the charterer after the ship is already on demurrage. A defective Notice of Readiness may prevent laytime from starting at all, unless it is cured by later conduct, waiver, new notice, or commencement of cargo operations under the charterparty.

The arithmetic should never be performed before the contract is read. The same Statement of Facts can produce different financial results under different charterparty terms. A calculation prepared under weather working days is not the same as one prepared under running days. A calculation under reversible laytime is not the same as one under separate load and discharge laytime. A calculation under despatch on all time saved is not the same as despatch on working time saved.

A professional laytime analyst therefore begins with the recap and charterparty, not with the time sheet. The time sheet is only the result. The governing charterparty wording determines what the time sheet should count, what it should ignore, and what rate should be applied to demurrage or despatch.

4. Practical Glossary for Laytime Calculation

Arrived Ship

A ship is an arrived ship when she has reached the contractual place where she may tender readiness. In a port charter, that may be the port or usual waiting place if the ship is within the port limits or otherwise qualifies under the clause. In a berth charter, the ship normally must reach the named berth unless wording such as WIBON or WIPON shifts the risk of berth unavailability. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for Arrived Ship is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

Notice of Readiness (NOR)

Notice of Readiness is the formal notice by which the master or agent states that the ship has arrived and is ready to load or discharge. It must be tendered to the correct party, at the correct place, in the permitted manner, and at a time allowed by the charterparty. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for Notice of Readiness is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

Notice Time

Notice time is the waiting period after a valid Notice of Readiness before laytime begins. It may be six hours, twelve hours, next working period, or another period stated in the charterparty. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for Notice Time is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

Weather Working Day

A weather working day is a working day or part of a working day during which weather permits the relevant cargo operation. The exact effect depends on whether the wording excludes periods when weather prevents work or excludes the whole working period. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for Weather Working Day is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

SHINC

SHINC means Sundays and holidays included. Under this wording, Sundays and holidays normally count unless another clause excludes them. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for SHINC is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

SHEX

SHEX means Sundays and holidays excluded. Under this wording, Sundays and holidays do not count as laytime unless used, depending on the precise words agreed. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for SHEX is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

Demurrage

Demurrage is the agreed amount payable to the shipowner for delay after laytime has expired, for which the shipowner is not responsible. It is usually calculated at a daily rate pro rata for part of a day. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for Demurrage is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

Despatch

Despatch is the agreed amount payable by the shipowner to the charterer where cargo operations finish before laytime expires. It is commonly half the demurrage rate, but this is only true if the charterparty says so. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for Despatch is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

Detention

Detention is a claim for damages for delay outside or beyond the demurrage regime, or for delay where demurrage is not the agreed remedy. Its availability depends on the facts and the contract. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for Detention is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

Reversible Laytime

Reversible laytime allows loading and discharging time to be combined so that unused time at one end may be used at the other end. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for Reversible Laytime is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

Average Laytime

Average laytime keeps load and discharge calculations separate but averages demurrage and despatch results at the end, producing a net financial balance. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for Average Laytime is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

Statement of Facts

The Statement of Facts records the chronological events of a port call. It is the raw evidence from which a time sheet is prepared. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for Statement of Facts is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

Time Sheet

The time sheet is the laytime calculation document. It applies the charterparty terms to the Statement of Facts to determine time used, time saved, demurrage, or despatch. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for Time Sheet is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

Once on Demurrage Always on Demurrage

This expression means that, after laytime has expired, many laytime exceptions no longer stop the running of demurrage unless the charterparty clearly provides that they do. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for Once on Demurrage Always on Demurrage is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

Free Pratique

Free pratique is health clearance or permission allowing the ship to communicate with shore. Whether it is required before a valid NOR depends on the charterparty and the facts. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for Free Pratique is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

Hold Readiness

Hold readiness means that the cargo spaces are clean, dry, safe, suitable, and legally ready to receive the cargo required by the charterparty. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for Hold Readiness is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

Port Charter

A port charter is a charter where the contractual destination for arrival is the port, rather than a specific berth. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for Port Charter is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

Berth Charter

A berth charter is a charter where the ship must reach the named or nominated berth before she is normally an arrived ship. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for Berth Charter is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

WIBON

WIBON means whether in berth or not. It is used to allow NOR and laytime risk to operate even if the ship cannot proceed directly to berth because the berth is unavailable. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for WIBON is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

WIPON

WIPON means whether in port or not. It may allow NOR to be tendered even when the ship is waiting outside the port due to congestion or restrictions, subject to the agreed wording. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for WIPON is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

WCCON

WCCON means whether customs cleared or not. It is intended to avoid disputes over customs clearance as a precondition to NOR. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for WCCON is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

WIFPON

WIFPON means whether in free pratique or not. It is intended to avoid disputes about free pratique as a precondition to NOR. In calculation work, this term should never be treated as a label only. The charterparty wording must be read to see whether the term is incorporated, amended, limited, or displaced by special rider clauses. A single added phrase in a recap can change the result of a claim by many hours or days.

The practical question for WIFPON is not only what the term means in general, but how it operates in the particular fixture. A broker, operator, port agent, owner or charterer should connect the term with the Statement of Facts, the time of each event, the relevant notices, and the exact laytime wording. This is why professional laytime work is both documentary and commercial.

5. Step-by-Step Method for Preparing a Laytime Calculation

Read the recap first: The recap often contains the commercial laytime agreement in compact form. It may state the cargo quantity, laycan, loading rate, discharging rate, demurrage rate, despatch rate, NOR rules, holidays, reversible or non-reversible laytime, and commission.
Read the charterparty form and riders: The printed form may contain default rules, but rider clauses often amend or override them. A laytime calculation that ignores rider clauses is unreliable.
Identify cargo quantity for laytime purposes: If laytime is calculated by rate, the cargo quantity determines the time allowed. The relevant quantity may be bill of lading quantity, shore scale quantity, draft survey quantity, or another agreed measurement.
Determine the allowed laytime: Convert the contractual allowance into days, hours and minutes. If the allowance is expressed as a rate per weather working day, divide the cargo quantity by the rate and convert the result.
Check arrived ship status: Confirm whether the ship had reached the contractual location when NOR was tendered. Consider port charter, berth charter, WIPON, WIBON and waiting-area wording.
Check the validity of NOR: Confirm readiness, timing, recipient, method, and supporting clearance requirements. If the first NOR was invalid, identify whether a later notice or conduct cured the problem.
Apply notice time: Count the waiting period after NOR according to the charterparty. Do not assume six hours unless the contract says so or the form provides it.
Create a chronological event table: Transfer events from the Statement of Facts into a time sheet. Include arrival, NOR, acceptance, berthing, commencement, stoppages, resumption, completion, shifting, and sailing.
Apply inclusions and exclusions: Count periods that count and deduct periods that do not count. Apply weather, holidays, strikes, breakdowns, shifting, waiting, and berth delays according to the charterparty.
Compare time used with time allowed: At each port and at the end of the voyage, determine whether the result is time saved, laytime used, or demurrage. Apply reversible or average rules if agreed.
Calculate money: Apply the daily demurrage or despatch rate pro rata. Check currency, payment time, taxes, commissions, and whether demurrage is also subject to brokerage.
Prepare supporting documents: Attach the charterparty, recap, Statement of Facts, NOR, letters of protest, weather evidence, port logs, holiday calendar, cargo documents, and calculation sheet.

Read the recap first. The recap often contains the commercial laytime agreement in compact form. It may state the cargo quantity, laycan, loading rate, discharging rate, demurrage rate, despatch rate, NOR rules, holidays, reversible or non-reversible laytime, and commission. This step should be documented rather than assumed. Laytime claims are often won or lost because one party can prove the sequence of events while the other party only relies on a general impression of what happened at the port. A clean calculation should allow another professional to follow the logic from the first line of the Statement of Facts to the final demurrage or despatch figure.

Read the charterparty form and riders. The printed form may contain default rules, but rider clauses often amend or override them. A laytime calculation that ignores rider clauses is unreliable. This step should be documented rather than assumed. Laytime claims are often won or lost because one party can prove the sequence of events while the other party only relies on a general impression of what happened at the port. A clean calculation should allow another professional to follow the logic from the first line of the Statement of Facts to the final demurrage or despatch figure.

Identify cargo quantity for laytime purposes. If laytime is calculated by rate, the cargo quantity determines the time allowed. The relevant quantity may be bill of lading quantity, shore scale quantity, draft survey quantity, or another agreed measurement. This step should be documented rather than assumed. Laytime claims are often won or lost because one party can prove the sequence of events while the other party only relies on a general impression of what happened at the port. A clean calculation should allow another professional to follow the logic from the first line of the Statement of Facts to the final demurrage or despatch figure.

Determine the allowed laytime. Convert the contractual allowance into days, hours and minutes. If the allowance is expressed as a rate per weather working day, divide the cargo quantity by the rate and convert the result. This step should be documented rather than assumed. Laytime claims are often won or lost because one party can prove the sequence of events while the other party only relies on a general impression of what happened at the port. A clean calculation should allow another professional to follow the logic from the first line of the Statement of Facts to the final demurrage or despatch figure.

Check arrived ship status. Confirm whether the ship had reached the contractual location when NOR was tendered. Consider port charter, berth charter, WIPON, WIBON and waiting-area wording. This step should be documented rather than assumed. Laytime claims are often won or lost because one party can prove the sequence of events while the other party only relies on a general impression of what happened at the port. A clean calculation should allow another professional to follow the logic from the first line of the Statement of Facts to the final demurrage or despatch figure.

Check the validity of NOR. Confirm readiness, timing, recipient, method, and supporting clearance requirements. If the first NOR was invalid, identify whether a later notice or conduct cured the problem. This step should be documented rather than assumed. Laytime claims are often won or lost because one party can prove the sequence of events while the other party only relies on a general impression of what happened at the port. A clean calculation should allow another professional to follow the logic from the first line of the Statement of Facts to the final demurrage or despatch figure.

Apply notice time. Count the waiting period after NOR according to the charterparty. Do not assume six hours unless the contract says so or the form provides it. This step should be documented rather than assumed. Laytime claims are often won or lost because one party can prove the sequence of events while the other party only relies on a general impression of what happened at the port. A clean calculation should allow another professional to follow the logic from the first line of the Statement of Facts to the final demurrage or despatch figure.

Create a chronological event table. Transfer events from the Statement of Facts into a time sheet. Include arrival, NOR, acceptance, berthing, commencement, stoppages, resumption, completion, shifting, and sailing. This step should be documented rather than assumed. Laytime claims are often won or lost because one party can prove the sequence of events while the other party only relies on a general impression of what happened at the port. A clean calculation should allow another professional to follow the logic from the first line of the Statement of Facts to the final demurrage or despatch figure.

Apply inclusions and exclusions. Count periods that count and deduct periods that do not count. Apply weather, holidays, strikes, breakdowns, shifting, waiting, and berth delays according to the charterparty. This step should be documented rather than assumed. Laytime claims are often won or lost because one party can prove the sequence of events while the other party only relies on a general impression of what happened at the port. A clean calculation should allow another professional to follow the logic from the first line of the Statement of Facts to the final demurrage or despatch figure.

Compare time used with time allowed. At each port and at the end of the voyage, determine whether the result is time saved, laytime used, or demurrage. Apply reversible or average rules if agreed. This step should be documented rather than assumed. Laytime claims are often won or lost because one party can prove the sequence of events while the other party only relies on a general impression of what happened at the port. A clean calculation should allow another professional to follow the logic from the first line of the Statement of Facts to the final demurrage or despatch figure.

Calculate money. Apply the daily demurrage or despatch rate pro rata. Check currency, payment time, taxes, commissions, and whether demurrage is also subject to brokerage. This step should be documented rather than assumed. Laytime claims are often won or lost because one party can prove the sequence of events while the other party only relies on a general impression of what happened at the port. A clean calculation should allow another professional to follow the logic from the first line of the Statement of Facts to the final demurrage or despatch figure.

Prepare supporting documents. Attach the charterparty, recap, Statement of Facts, NOR, letters of protest, weather evidence, port logs, holiday calendar, cargo documents, and calculation sheet. This step should be documented rather than assumed. Laytime claims are often won or lost because one party can prove the sequence of events while the other party only relies on a general impression of what happened at the port. A clean calculation should allow another professional to follow the logic from the first line of the Statement of Facts to the final demurrage or despatch figure.

6. Fixed Laytime and Rate-Based Laytime

Fixed laytime gives a stated number of days or hours for loading or discharging. Rate-based laytime gives a productivity rate and converts cargo quantity into an allowed period. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

The first practical task is to isolate the relevant clause. A broker may remember the abbreviation, an operator may remember the port event, and a master may remember the operational difficulty, but the calculation must bring all of these together. If the clause says that time stops, the time sheet should stop it. If the clause says time counts, the time sheet should count it. If the clause is silent, the answer may depend on general law and established chartering practice.

Disputes often arise because the same event has two possible descriptions. Rain may be a weather interruption, but it may also be irrelevant if the cargo was not ready or if the ship was already on demurrage. Waiting outside port may be congestion, but it may also be time before arrival if the charter is a strict berth charter without protective wording. A holiday may be excluded, but if cargo is actually worked the result may change under the agreed abbreviation.

From a drafting point of view, this topic should be addressed before the fixture is concluded. The parties should avoid relying on habit or memory. If they intend time to count during a particular event, the clause should say so. If they intend time to be excluded, the clause should say so. Clear wording reduces later demurrage disputes and makes the time sheet easier to prepare.

From an operational point of view, all related facts should be recorded in the Statement of Facts, port logs, NOR records, protest letters and correspondence. The calculation is only as strong as the evidence behind it. When a time sheet is challenged months after the voyage, the party with precise records usually has a much stronger position than the party relying on general recollection.

7. Running Days, Working Days and Weather Working Days

The expression used for the laytime unit changes the counting method. Running days usually count continuously, working days depend on port working practice, and weather working days depend on the effect of weather on cargo operations. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

8. Sundays and Holidays in Laytime Calculation

Sundays and holidays can change the result dramatically. SHINC, SHEX, SSHINC, SHEX EIU and similar abbreviations should be read with local holiday calendars and the actual hours worked. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

9. Notice of Readiness as the Starting Point

NOR is often the gateway to laytime. Without a valid NOR, laytime may not commence, even if the ship physically waits for cargo. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

10. Arrived Ship: Port Charter and Berth Charter

Before NOR can start laytime, the ship must generally be an arrived ship. The distinction between port and berth charters explains many waiting-time disputes. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

11. Physical Readiness and Legal Readiness

Readiness includes not only arrival but also the ship’s ability to load or discharge the agreed cargo. Holds, documents, crew, gear, clearances and compliance may all matter. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

12. Hold Inspection and Failed Holds

A failed hold inspection can prevent a valid NOR or interrupt laytime depending on the contract. Modern forms may contain special provisions for hold reinspection and cancellation. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

13. Notice Time and Commencement of Laytime

Many charterparties provide that laytime begins after a fixed notice period. Cargo operations commencing earlier may trigger immediate or partial counting depending on wording. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

14. Time Counting During Waiting for Berth

Waiting for berth is one of the main commercial risks in voyage chartering. WIPON, WIBON, berth congestion clauses and port-charter wording allocate this risk. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

15. Weather Interruptions

Weather clauses require careful analysis. The relevant question is not simply whether rain fell, but whether weather prevented the contractual cargo operation during a time that would otherwise have counted. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

16. Strikes, Congestion and Port Restrictions

Labour stoppages, port congestion, equipment shortages and administrative delays can affect laytime only if the charterparty allocates the risk to one party or the other. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

17. Shifting Time, Berthing and Unberthing

Shifting within port may be for the shipowner’s purpose, the charterer’s purpose, or port authority convenience. The contract and facts determine whether time counts. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

18. Draft Survey, Ullage, Sampling and Documentation

Cargo measurement and documentation events may be part of cargo operations or separate interruptions. Their treatment should be addressed in the time sheet. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

19. Reversible Laytime

Reversible laytime allows the charterer to use unused loading time at discharge. It is common in tanker trades and less common in many dry bulk fixtures. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

20. Average Laytime

Average laytime is different from reversible laytime. The load and discharge calculations are prepared separately and then the financial results are averaged. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

21. Non-Reversible Laytime

In many dry bulk fixtures, loading laytime and discharging laytime are separate. Time saved at one end cannot be used at the other unless the charterparty permits it. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

22. Demurrage Calculation

Demurrage is calculated when laytime expires. The daily rate is applied pro rata unless the charterparty provides another method. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

23. Despatch Calculation

Despatch requires an express agreement. The main question is whether despatch is payable on all time saved, working time saved, or only laytime saved. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

24. Detention Compared with Demurrage

Detention may apply where the delay falls outside the demurrage bargain or where the charterer breaches a separate duty. It is not simply another name for demurrage. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

25. Statement of Facts

The Statement of Facts is the central port document. It records arrival, notices, berthing, commencement, stoppages, resumption, completion and other events. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

26. Time Sheet Construction

The time sheet translates the Statement of Facts into a contractual calculation. It should be transparent, chronological and consistent with the charterparty. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

27. Dry Bulk Laytime Practice

Dry bulk calculations often involve loading/discharging rates, grain elevators, grabs, weather exceptions, hold inspections, trimming, draft surveys and port congestion. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

28. Tanker Laytime Practice

Tanker laytime often involves shorter laycans, NOR at anchorage, pumping warranties, ullaging, sampling, hoses, shore restrictions, shifting and reversible time. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

29. GENCON Laytime Themes

GENCON voyage chartering requires close attention to NOR, laydays, cancelling, cargo readiness, laytime, demurrage and exceptions. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

30. ASBATANKVOY Laytime Themes

ASBATANKVOY practice often focuses on clause 5 laydays, clause 6 NOR, six-hour notice time, pumping, shifting and berth waiting. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

31. BIMCO Laytime Definitions

BIMCO Laytime Definitions for Charter Parties 2013 give standard meanings to commonly used expressions and help reduce disputes where incorporated. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

32. Evidence and Burden of Proof

Laytime claims depend on evidence. The party claiming demurrage or despatch must connect the facts with the contract and prove the calculation. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

33. Letters of Protest

Letters of protest preserve disagreement about events such as invalid NOR, rain stoppages, berth delays, cargo unavailability, failed holds or slow discharge. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

34. Common Calculation Mistakes

Most laytime mistakes arise from using the wrong start time, ignoring holidays, treating reversible time incorrectly, or applying exceptions after demurrage starts. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

35. Practical Negotiation of Laytime Clauses

Good laytime drafting begins before fixture. The parties should specify the allowance, abbreviations, exceptions, NOR rules, despatch basis and documents required. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

36. Laytime and Voyage Estimating

A voyage estimate is incomplete unless it considers expected port time, demurrage risk, despatch exposure, congestion, weather season and berth productivity. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

37. Time Bars for Demurrage Claims

Many charterparties impose a documentary time bar for demurrage claims. Missing the deadline may defeat an otherwise valid claim. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

38. Digital Laytime Systems

Digital systems can reduce arithmetic errors, but they cannot replace contractual judgment. The software must be configured to the actual charterparty. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

39. Practical Checklist for Shipowners

Shipowners should protect laytime by monitoring arrival, readiness, NOR, SOF entries, protests, stoppages, completion and documentary deadlines. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

40. Practical Checklist for Charterers

Charterers should protect themselves by reviewing NOR validity, ensuring the SOF is accurate, recording exceptions, checking calculations and submitting despatch claims correctly. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

41. Practical Checklist for Port Agents

Port agents should record events neutrally, accurately and immediately. The agent’s Statement of Facts may become the most important document in the demurrage file. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

42. Conclusion

Laytime calculation is a discipline that combines contract reading, port practice, arithmetic, evidence and commercial judgment. In a professional calculation, this subject should be approached with reference to both the charterparty and the actual port chronology. It is rarely enough to know the general rule, because the parties may have modified the rule in the recap, the printed form, or the rider clauses. The correct result depends on the words agreed, the facts recorded, and the way those facts are matched to the agreed words.

43. Worked Example 1: Fixed Laytime for Loading and Discharging

Assume a voyage charter provides 4 running days for loading and 5 running days for discharging. Demurrage is USD 12,000 per day pro rata, despatch is half demurrage on laytime saved, and the laytime is non-reversible. The ship tenders valid Notice of Readiness at the load port on Monday at 06:00. The charterparty provides six hours’ notice time. Laytime therefore begins at 12:00 on Monday.

Loading completes on Thursday at 18:00. From Monday 12:00 to Thursday 18:00, the time used is 3 days and 6 hours. The loading allowance is 4 days. The charterer saves 18 hours at the load port. Because the laytime is non-reversible, this saved loading time cannot be carried to discharge unless the charterparty says otherwise. It may, however, generate despatch if despatch is agreed.

The ship tenders valid NOR at the discharge port on the following Wednesday at 08:00. Six hours’ notice time expires at 14:00. Discharging completes the next Tuesday at 02:00. The time used is 5 days and 12 hours. The discharge allowance is 5 days. The charterer is on demurrage for 12 hours at discharge.

The loading despatch is 18 hours at half demurrage. Half of USD 12,000 is USD 6,000 per day. Eighteen hours is 0.75 of a day, so loading despatch is USD 4,500. Discharge demurrage is 12 hours at USD 12,000 per day. Twelve hours is 0.5 of a day, so discharge demurrage is USD 6,000. Because the charterparty is non-reversible and unless it provides for averaging, the owner may claim USD 6,000 demurrage and the charterer may claim USD 4,500 despatch as separate results.

This example shows why the labels non-reversible, reversible and average are commercially important. The same port chronology can produce a different financial result if the contract combines the allowed time or averages the result. The calculation is not only arithmetic; it is the application of a legal bargain to port facts.

Event	Time	Effect
Valid NOR at load port	Monday 06:00	Notice time begins
Laytime starts	Monday 12:00	Six hours after NOR
Loading complete	Thursday 18:00	3 days 6 hours used
Loading result	18 hours saved	Possible despatch
Discharge laytime starts	Wednesday 14:00	Six hours after NOR
Discharge complete	Tuesday 02:00	5 days 12 hours used
Discharge result	12 hours demurrage	Owner’s claim

44. Worked Example 2: Laytime Allowed by Loading Rate

Assume a dry bulk cargo order states 30,000 metric tons of bulk grain, loading at 10,000 metric tons per weather working day of 24 consecutive hours, Sundays and holidays excluded unless used, discharging at 6,000 metric tons per weather working day of 24 consecutive hours, Sundays and holidays included. Demurrage is USD 15,000 per day and despatch is USD 7,500 per day on working time saved.

At loading, the laytime allowance is calculated by dividing 30,000 metric tons by 10,000 metric tons per day. The result is 3 weather working days. Three days equals 72 hours. Because Sundays and holidays are excluded unless used, the time sheet must examine each stoppage, each working period, and each excluded day. If the port works during an excluded period and the wording says unless used, the used period may count.

At discharging, the allowance is 30,000 metric tons divided by 6,000 metric tons per day. The result is 5 weather working days, or 120 hours. Since Sundays and holidays are included at discharge, those days count unless stopped by weather or another agreed exception. A charterer who assumes that Sundays do not count at discharge would make a serious calculation error.

Suppose load port laytime starts Tuesday at 08:00. Rain stops loading from Tuesday 18:00 to Wednesday 02:00. The port holiday runs Thursday 00:00 to Thursday 24:00, and no work is done. Loading completes Friday at 12:00. The Tuesday rain interruption of 8 hours does not count if weather prevented loading. The Thursday holiday does not count if SHEX unless used applies and no work took place. The time sheet must count only the eligible time from the chronological record.

Suppose discharge laytime starts Monday at 06:00 and completion occurs Saturday at 12:00 with no weather interruption. Because Sundays and holidays are included and the operation ended before Sunday, all time from Monday 06:00 to Saturday 12:00 counts. That is 5 days and 6 hours. The discharge allowance is 5 days, so there are 6 hours of demurrage at USD 15,000 per day, or USD 3,750. The result is straightforward only because the clause has been applied carefully.

45. Worked Example 3: Reversible Laytime

Assume a tanker voyage provides 72 hours total laytime, reversible for loading and discharging, demurrage USD 30,000 per day pro rata. Loading uses 20 hours after commencement of laytime. Discharging uses 60 hours after commencement of discharge laytime. Total time used is therefore 80 hours. The combined allowance is 72 hours. The charterer has exceeded laytime by 8 hours.

The demurrage calculation is 8 hours divided by 24 hours, multiplied by USD 30,000. The monetary result is USD 10,000. The important point is that the charterer did not go on demurrage at the load port even though some operational period may have been longer or shorter than expected. Under reversible laytime, the two ends are examined together, unless the charterparty contains a specific provision to the contrary.

Reversible laytime is commercially useful where loading and discharging operations are part of one combined port-time bargain. It is particularly common in tanker forms, but the exact wording must still be checked. The presence of the word reversible is not a substitute for reading the clause. The calculation must also identify whether waiting time, shifting, hose connection, sampling, pumping stoppages and documentation periods count under the relevant tanker form.

If the same facts were calculated under separate laytime, the result might be different. If the loading allowance had been 36 hours and discharge allowance 36 hours, loading would show 16 hours saved and discharge would show 24 hours demurrage. Depending on despatch and averaging wording, the financial result could differ from the simple reversible result. This is why laytime structure is a key fixture term, not a clerical detail.

46. Worked Example 4: Average Laytime

Average laytime is often confused with reversible laytime, but the calculation logic is different. In average laytime, the loading and discharging calculations are prepared separately. The demurrage at one end and despatch at the other end are then set off against each other according to the charterparty wording. The parties do not simply combine all allowed hours at the beginning.

Assume loading allowance is 48 hours and loading uses 40 hours, creating 8 hours saved. Discharge allowance is 60 hours and discharge uses 72 hours, creating 12 hours on demurrage. Demurrage is USD 24,000 per day and despatch is half demurrage. If average laytime applies in a way that averages time, the net result may be 4 hours demurrage. If average laytime applies financially, the calculation may compare 12 hours demurrage value with 8 hours despatch value at half rate. The exact clause matters.

This example shows why the word average should not be used loosely. Some recaps say reversible when the parties mean average, and some say average when the parties mean reversible. If a dispute later arises, the written terms will be examined closely. A professional recap should state exactly how the parties intend to calculate the result.

47. Worked Example 5: Invalid Notice of Readiness

Assume a ship arrives at the load port anchorage on Monday at 04:00 and tenders NOR at 04:30. The charterparty is a berth charter and does not contain WIBON, WIPON or similar wording. The named berth is occupied. The ship remains at anchorage until Thursday and berths Thursday at 10:00. Loading starts Thursday at 16:00. The owner argues that laytime began Monday after notice time. The charterer argues that the NOR was premature.

If the charter is truly a berth charter and the ship had to reach the berth before being an arrived ship, the Monday NOR may be invalid. Unless the charterparty or later conduct cures the defect, laytime may not start from that notice. If loading begins Thursday at 16:00, the commencement of loading may operate as a practical trigger under some clauses or legal principles, but the exact result depends on the contract and facts.

The lesson is that operators should not treat NOR as a routine form. The master and agent should know whether the charter is a port charter or berth charter, whether WIPON, WIBON, WCCON, WIFPON or reachable-on-arrival wording exists, and who must receive the notice. If there is doubt, the master may tender protective notices without prejudice, but this should be done in a disciplined way and in accordance with the contract.

48. Worked Example 6: Weather Working Day

Assume a charterparty allows 3 weather working days for loading, Sundays and holidays included. Laytime starts Monday at 06:00. The port works continuously except for rain from Monday 12:00 to Monday 18:00 and strong wind from Tuesday 04:00 to Tuesday 10:00, both of which stop loading. Loading completes Thursday at 02:00. The total elapsed time from Monday 06:00 to Thursday 02:00 is 68 hours.

If the weather wording excludes periods during which weather prevents loading, 12 hours are deducted for the two weather stoppages. The counted time is therefore 56 hours. The allowed time is 72 hours. The charterer has 16 hours saved. If despatch is agreed on all laytime saved, the charterer may claim despatch for 16 hours. If despatch is on working time saved, the calculation may require a narrower analysis.

The calculation changes if the weather was bad but loading would not have been possible for another reason, such as unavailable cargo, broken ship gear, or a port closure not caused by weather. A weather exception usually requires a causal connection between weather and the inability to perform the relevant cargo operation. A rain entry in the Statement of Facts is not automatically a laytime deduction.

49. Clause-by-Clause Issues That Affect Laytime Calculation

Cargo quantity and laytime allowance

Cargo quantity and laytime allowance should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, cargo quantity and laytime allowance can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Loading rate and discharging rate

Loading rate and discharging rate should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, loading rate and discharging rate can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Per hatch per day calculations

Per hatch per day calculations should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, per hatch per day calculations can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Customary quick despatch

Customary quick despatch should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, customary quick despatch can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Running hours and consecutive hours

Running hours and consecutive hours should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, running hours and consecutive hours can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Berth terms and port terms

Berth terms and port terms should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, berth terms and port terms can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

WIPON and waiting outside port

WIPON and waiting outside port should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, wipon and waiting outside port can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

WIBON and waiting for berth

WIBON and waiting for berth should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, wibon and waiting for berth can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

WCCON and customs clearance

WCCON and customs clearance should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, wccon and customs clearance can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

WIFPON and free pratique

WIFPON and free pratique should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, wifpon and free pratique can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Time lost waiting for berth

Time lost waiting for berth should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, time lost waiting for berth can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Time lost due to weather

Time lost due to weather should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, time lost due to weather can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Time lost due to strikes

Time lost due to strikes should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, time lost due to strikes can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Time lost due to ship breakdown

Time lost due to ship breakdown should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, time lost due to ship breakdown can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Time lost due to shore equipment failure

Time lost due to shore equipment failure should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, time lost due to shore equipment failure can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Time lost due to cargo unavailability

Time lost due to cargo unavailability should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, time lost due to cargo unavailability can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Time lost due to draft survey

Time lost due to draft survey should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, time lost due to draft survey can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Time lost due to fumigation

Time lost due to fumigation should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, time lost due to fumigation can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Time lost due to shifting

Time lost due to shifting should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, time lost due to shifting can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Time lost due to lightening

Time lost due to lightening should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, time lost due to lightening can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Time lost due to hold cleaning

Time lost due to hold cleaning should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, time lost due to hold cleaning can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Time lost due to hatch-cover testing

Time lost due to hatch-cover testing should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, time lost due to hatch-cover testing can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Time lost due to port authority orders

Time lost due to port authority orders should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, time lost due to port authority orders can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Time lost due to quarantine

Time lost due to quarantine should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, time lost due to quarantine can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Time lost due to bad stowage

Time lost due to bad stowage should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, time lost due to bad stowage can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Time lost due to trim and stability restrictions

Time lost due to trim and stability restrictions should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, time lost due to trim and stability restrictions can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Time lost due to waiting documents

Time lost due to waiting documents should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, time lost due to waiting documents can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Time lost after completion of cargo operations

Time lost after completion of cargo operations should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, time lost after completion of cargo operations can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Demurrage rate and currency

Demurrage rate and currency should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, demurrage rate and currency can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Despatch rate and basis

Despatch rate and basis should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, despatch rate and basis can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Claim supporting documents

Claim supporting documents should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, claim supporting documents can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

Demurrage claim time bar

Demurrage claim time bar should be considered as a separate calculation issue. The time sheet should not simply copy the Statement of Facts and total the hours. It should ask whether this event is covered by the laytime clause, by a rider clause, by the printed charterparty form, or by a special recap term. If the event is not addressed directly, the analyst must consider whether general chartering principles supply an answer.

In practice, demurrage claim time bar can affect the result in more than one way. It may change the commencement of laytime, interrupt time that has already started, accelerate demurrage, prevent despatch, or create a separate damages claim. The port agent’s description should therefore be precise. Expressions such as waiting, stopped, no work, rain, shore delay, cargo not ready, or documents pending should be supported by times, causes, and where possible, written confirmation.

50. Sample Time Sheet Layout for a Dry Bulk Voyage

A time sheet should be clear enough for another person to audit. The following simplified layout shows how a dry bulk loading calculation may be presented. In a real file, each entry should be supported by the Statement of Facts and relevant documents.

Date	Time From	Time To	Event	Counted Time	Remarks
01 July	06:00	12:00	Notice time after valid NOR	0:00	Notice period
01 July	12:00	18:00	Laytime running, loading commenced	6:00	Counts
01 July	18:00	22:00	Rain stopped loading	0:00	Weather exception
01 July	22:00	24:00	Loading resumed	2:00	Counts
02 July	00:00	24:00	Loading continued	24:00	Counts
03 July	00:00	08:00	Holiday, no work	0:00	Excluded under SHEX
03 July	08:00	20:00	Holiday worked by agreement	12:00	Counts if SHEX unless used
04 July	00:00	06:00	Loading completed	6:00	Counts

This type of layout prevents hidden assumptions. It shows the event, the time, the counting treatment, and the reason. A calculation that only states total laytime used without explaining each deduction is much easier to challenge.

51. Special Practical Issues in Laytime Calculation

Laytime and Cargo Readiness

Cargo readiness is often the charterer’s responsibility, but the impact on laytime depends on whether the ship has validly arrived and tendered readiness. If the cargo is not available before laytime begins, the shipowner may have no laytime claim for that earlier period. Once laytime has begun, cargo unavailability may count against the charterer unless protected by an exception.

The practical treatment of laytime and cargo readiness should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and cargo readiness should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Ship Readiness

The ship must be ready in the contractual sense. If the holds are dirty, the pumping system cannot perform, the cranes are defective where ship’s gear is required, or documents prevent cargo work, NOR may be invalid or time may be for the owner’s account.

The practical treatment of laytime and ship readiness should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and ship readiness should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Cargo Documents

Bills of lading, mate’s receipts, customs documents, certificates, letters of indemnity and export documents may all influence completion and sailing. Whether time spent waiting for documents counts depends on the charterparty and the reason for the delay.

The practical treatment of laytime and cargo documents should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and cargo documents should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Port Congestion

Congestion is a classic source of demurrage disputes. A port charter with WIPON or congestion wording may put the risk on the charterer earlier than a strict berth charter would.

The practical treatment of laytime and port congestion should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and port congestion should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Holidays

Holiday treatment requires local knowledge. A national holiday, local religious holiday, port holiday or labour holiday may not have the same effect under every charterparty.

The practical treatment of laytime and holidays should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and holidays should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Weather Logs

Weather evidence should be recorded with times and effects. The strongest record states not only that rain occurred, but that the rain prevented loading or discharging of the particular cargo.

The practical treatment of laytime and weather logs should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and weather logs should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Grain Cargoes

Grain trades often involve high-speed loading, trimming, fumigation, hold inspection, draft surveys and strict cleanliness. Despatch exposure can be large where loading terminals operate efficiently.

The practical treatment of laytime and grain cargoes should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and grain cargoes should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Coal Cargoes

Coal cargoes may involve trimming, sampling, moisture declarations, self-heating precautions, and berth delays. The cargo condition may also affect whether operations can safely proceed.

The practical treatment of laytime and coal cargoes should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and coal cargoes should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Iron Ore

Iron ore loading can be extremely fast, but draft surveys, ballast operations, terminal queues and cargo documentation can affect time. Because loading speed may be high, small delays can still become material.

The practical treatment of laytime and iron ore should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and iron ore should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Fertilizers

Fertilizer cargoes require dry holds and careful weather protection. Rain interruptions may be frequent and should be recorded accurately.

The practical treatment of laytime and fertilizers should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and fertilizers should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Steel Cargoes

Steel cargo loading may stop for rain to avoid wet damage. The wording should clarify weather exceptions and responsibility for dunnage, lashing, tallying and securing.

The practical treatment of laytime and steel cargoes should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and steel cargoes should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Tanker Pumping

Tanker discharge calculations often require analysis of pumping rates, shore back pressure, line displacement, sampling, ullaging, hose connection and disconnection.

The practical treatment of laytime and tanker pumping should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and tanker pumping should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Multiple Ports

Multiple load or discharge ports require careful separation of events. The charterparty may provide total laytime for all ports, separate allowances, or special rules for shifting and waiting between berths.

The practical treatment of laytime and multiple ports should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and multiple ports should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Part Cargoes

Where the ship carries part cargoes for different charterers, the SOF and time sheet must distinguish which delay belongs to which cargo interest.

The practical treatment of laytime and part cargoes should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and part cargoes should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Deadfreight

Deadfreight may arise when the charterer supplies less cargo than agreed. The laytime allowance may then depend on the contractual quantity, the loaded quantity, or special wording.

The practical treatment of laytime and deadfreight should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and deadfreight should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Freight Payment

Demurrage and despatch are separate from freight, but they affect voyage economics. Commission may also apply to demurrage if the charterparty says so.

The practical treatment of laytime and freight payment should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and freight payment should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Bills of Lading

Bills of lading may incorporate charterparty terms, but incorporation wording must be checked. Laytime disputes under the charterparty are not automatically transferred to bill holders.

The practical treatment of laytime and bills of lading should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and bills of lading should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Safe Port Risk

Unsafe port issues may create delay, damages, or cancellation questions. Laytime calculation may not answer the entire dispute if the underlying breach is safe-port related.

The practical treatment of laytime and safe port risk should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and safe port risk should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Sanctions

Sanctions checks, port restrictions or cargo legality issues may delay operations. Modern clauses may allocate risk expressly, and time-sheet treatment must follow the clause.

The practical treatment of laytime and sanctions should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and sanctions should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Emissions

Port delays affect fuel consumption and emissions performance. Modern voyage planning increasingly considers just-in-time arrival and carbon-intensity consequences, but the laytime bargain still controls demurrage unless amended.

The practical treatment of laytime and emissions should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and emissions should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Arbitration

Arbitrators often examine the exact words of the charterparty, the chronology, the contemporaneous documents and the calculation method. A well-prepared laytime file is easier to defend.

The practical treatment of laytime and arbitration should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and arbitration should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Settlement

Many demurrage disputes settle commercially. A transparent time sheet helps settlement because it allows each side to identify genuine points of difference.

The practical treatment of laytime and settlement should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and settlement should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Training

Junior operators should learn laytime by preparing calculations manually before relying on software. Manual work teaches the relationship between clauses, facts and money.

The practical treatment of laytime and training should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and training should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

Laytime and Internal Controls

Companies should have standard review procedures for demurrage claims, including document checklists, time-bar diaries, approval thresholds and claim templates.

The practical treatment of laytime and internal controls should be recorded clearly in the calculation. If the event counts, the time sheet should say why it counts. If the event is excluded, the time sheet should identify the clause or factual basis for exclusion. Clear reasoning is particularly important where the event occurred near the start of laytime, near the expiry of laytime, or after the ship had already gone on demurrage.

In commercial negotiations, laytime and internal controls should be anticipated wherever possible. A fixture recap that deals with likely port events in advance is usually more valuable than a lengthy argument after the voyage. The party that understands the risk before fixing can price it, insure it, avoid it, or allocate it by express wording.

52. Frequently Asked Questions About Laytime Calculation

What is laytime in shipping?

Laytime is the contractual time allowed to the charterer for loading and discharging without paying demurrage. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

Where the financial amount is significant, the parties should preserve all evidence: NOR, SOF, port logs, weather records, holiday calendars, terminal statements, letters of protest, e-mail correspondence, and the final time sheet. A clear documentary file reduces the risk of a disputed claim and helps both sides evaluate settlement.

What is laytime calculation?

Laytime calculation is the process of applying the charterparty to the port chronology in order to determine time used, time saved, demurrage or despatch. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

When does laytime start?

Laytime usually starts when the ship has arrived, is ready, has tendered a valid Notice of Readiness, and any agreed notice time has expired. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

Can laytime start before the laydays?

Usually not unless the charterparty permits it, the charterer sanctions it, or cargo operations commence in circumstances covered by the contract. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

Does rain always stop laytime?

No. Rain stops laytime only if the charterparty weather wording applies and the rain prevents the relevant cargo operation during time that would otherwise count. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

Do Sundays count as laytime?

They count or do not count depending on the wording. SHINC includes them. SHEX excludes them unless the wording or actual use changes the result. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

What is demurrage?

Demurrage is the agreed sum payable to the owner after laytime has expired for delay not caused by the owner. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

What is despatch?

Despatch is a payment from the owner to the charterer for completing cargo operations before allowed laytime expires, if the charterparty provides for it. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

What is detention?

Detention is damages for delay that falls outside the agreed laytime and demurrage mechanism or arises from a separate breach. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

What is reversible laytime?

Reversible laytime combines the load and discharge allowances so that unused time at one end can be used at the other. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

What is average laytime?

Average laytime calculates loading and discharging separately and then averages or sets off the results as provided in the charterparty. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

What is a Statement of Facts?

A Statement of Facts is the port chronology recording events relevant to laytime, demurrage and despatch. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

Who prepares the time sheet?

The time sheet may be prepared by owners, charterers, brokers, operators or agents, but it must follow the charterparty. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

Can demurrage be time-barred?

Yes. Many charterparties contain strict documentary time bars requiring claims and supporting documents within a fixed period. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

Does once on demurrage always on demurrage apply to every case?

It is a common principle, but exceptions may still apply if the charterparty expressly states that they interrupt demurrage. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

Does loading commencement cure a bad NOR?

Sometimes the commencement of cargo operations may affect the position, but the result depends on the charterparty and the facts. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

What is all time saved despatch?

It means despatch is calculated by comparing completion time with expiry of laytime including non-working time, unless modified. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

What is working time saved despatch?

It means despatch is calculated only on working time saved, excluding periods that would not have counted as laytime. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

What is laytime allowed by rate?

It is allowed time calculated by dividing cargo quantity by the agreed loading or discharging rate. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

What is a port charter?

A port charter allows arrival at the port or agreed waiting place to be relevant for NOR, depending on the wording. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

What is a berth charter?

A berth charter generally requires arrival at the berth before NOR is valid unless protective wording changes the position. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

Why is the SOF important?

Because it is the main evidence of the port events from which the laytime calculation is prepared. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

Can a port agent decide laytime?

No. The agent records facts. The charterparty decides how those facts are treated. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

Should laytime be calculated manually or by software?

Software can help arithmetic, but the legal and contractual judgment must come from the user. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

What is the biggest error in laytime claims?

The biggest error is counting time mechanically without first checking whether NOR was valid and which periods count under the charterparty. The practical answer may change if the charterparty uses special wording. For that reason, a professional calculation should always begin with the recap, the printed form, the rider clauses and the Statement of Facts. General definitions are useful, but the contract controls the final result.

53. Master Checklist for Laytime Calculation

Confirm the governing charterparty form and all rider clauses.
Check whether the fixture recap amends the printed laytime wording.
Identify the cargo quantity used to calculate laytime.
Confirm whether laytime is fixed, rate-based, reversible, averageable or separate.
Check whether the charter is a port charter or berth charter.
Check whether WIPON, WIBON, WCCON, WIFPON or similar wording applies.
Confirm the exact date and time of arrival at port, anchorage or berth.
Confirm whether the ship was physically ready and legally ready.
Check whether free pratique, customs clearance, hold approval or other formalities affected NOR.
Confirm the time, method and recipient of each NOR.
Apply notice time exactly as stated in the charterparty.
Check the opening of laydays and the cancelling date.
Record when cargo operations actually commenced.
Record all stoppages with precise reasons and times.
Separate weather stoppages from non-weather stoppages.
Check Sundays, holidays and local working calendars.
Confirm whether excluded periods were actually used.
Check whether the ship was on demurrage before applying exceptions.
Calculate time used at each port.
Apply reversible or average laytime if agreed.
Calculate demurrage or despatch pro rata.
Check whether despatch is all time saved or working time saved.
Check whether commission applies to demurrage.
Check the claim time bar and required documents.
Review the final calculation before sending the claim.

This checklist is deliberately detailed because laytime mistakes are rarely caused by difficult arithmetic. They are usually caused by omitted facts, assumed wording, missing documents or incorrect treatment of a period. A calculation prepared quickly without a checklist may look convincing but fail when challenged.

The checklist also supports internal risk management. Chartering teams, operations teams, claims teams and brokers can use the same structure, which makes communication easier. A consistent method reduces the chance that one person treats a holiday, weather interruption or NOR defect differently from another person in the same company.

Most importantly, the checklist encourages contemporaneous record-keeping. A laytime dispute is not usually solved by clever argument alone. It is solved by a combination of contract wording, accurate chronology and credible evidence.

54. Final Guidance on Laytime Calculation in Ship Chartering

Laytime calculation in ship chartering is a practical discipline built on three foundations: the charterparty, the Statement of Facts and commercial judgment. The charterparty tells the parties what was agreed. The Statement of Facts shows what happened. Commercial judgment explains how the agreed words should be applied to the recorded events in a way that is coherent, defensible and commercially realistic.

A good laytime calculation should be transparent. It should show when laytime began, why it began at that time, what periods counted, what periods were excluded, when laytime expired, whether the ship went on demurrage, whether despatch was earned, and how the final money figure was calculated. Anyone reading the calculation should be able to follow the logic without guessing what the analyst assumed.

The most common disputes are avoidable. They arise from unclear recaps, incomplete Statements of Facts, casual use of abbreviations, invalid NOR, uncertain weather records, incorrect holiday treatment, confusion between reversible and average laytime, and missed demurrage time bars. These problems can be reduced by careful drafting, disciplined port documentation and early review of the laytime position while evidence is still available.

BIMCO definitions and standard forms provide useful structure, but they do not remove the need to read the agreed charterparty. Every fixture has its own commercial pattern, and every port call has its own chronology. The professional skill lies in connecting the general principles to the particular contract and the particular facts.

In voyage chartering, time is money. Laytime decides when the charterer’s free cargo-operation time ends and when additional payment begins. For that reason, laytime calculation should be treated as a core chartering skill, not an administrative afterthought. Owners, charterers, brokers, masters, agents and claims handlers all benefit when the calculation is accurate, logical, well-documented and prepared with a full understanding of the charterparty.