Demurrage and Laytime in Shipping: Key Aspects and Calculations

In maritime shipping, time is literally money. The concepts of laytime and demurrage are fundamental to commercial shipping operations and represent a critical area of focus for maritime lawyers, shipowners (commonly called “Owners” in legal documents), and charterers alike. This article examines these concepts under English law, which remains the predominant legal framework for international shipping contracts worldwide.

Understanding Key Definitions

Before turning to the details, consider a simple taxi analogy. The first few minutes the driver waits are free. If the passenger keeps the vehicle waiting beyond that, a delay fee starts to accrue. In shipping, the same logic applies: once the agreed free window expires, a daily charge is payable until cargo operations finish.

Laytime

According to BIMCO’s official definition (the Baltic and International Maritime Council — the shipping industry’s main trade body that drafts standard contracts), laytime is “the period of time agreed between the parties during which the Owner will make and keep the vessel available for loading or discharging without payment additional to the freight.” It represents the “free time” allocated for cargo operations.

To put this in everyday terms: imagine you’ve ordered a taxi to take you to the airport. The driver arrives at your location and waits. You have an agreed amount of “free time” (say, 5 minutes) to come down from your apartment, load your luggage, and get in the car without any extra charges. This waiting time is like laytime — it’s included in the basic service price.

In shipping, when a vessel arrives at port, the charterer (the party who hired the vessel) gets a predetermined amount of “free time” to complete loading or discharging operations. This could be 24 hours, 48 hours, or calculated based on the cargo quantity (e.g., 1,500 tons per day).

Demurrage

When the allowed time expires and cargo operations are still ongoing, demurrage becomes payable. BIMCO defines demurrage as “an agreed amount payable to the Owner in respect of delay to the vessel beyond the laytime, for which the Owner is not responsible.“

Continuing the taxi analogy: if you exceed the five-minute grace period because you cannot find your passport or your luggage is heavier than expected, the driver starts to apply a waiting fee. The meter runs and you pay a predetermined amount for every additional minute.

In shipping terms, if cargo operations take longer than the agreed time, the charterer must pay the shipowner a daily charge for every additional day or part thereof. Typical rates can range from a few thousand to tens of thousands of dollars per day, depending on the vessel size and market conditions.

Despatch

The counterpart to demurrage is despatch. This is the amount payable by the shipowner to the charterer when cargo operations are completed before the free time expires. Typically calculated at half the demurrage rate, despatch serves as an incentive for charterers to work efficiently.

Here’s where our taxi analogy breaks down slightly — imagine if Uber actually paid you money for being ready early! Alas, in reality, taxi apps don’t reward punctual passengers, but shipping does.

If a charterer completes cargo operations faster than the allowed time, the shipowner pays them despatch money as a reward for efficiency. For example, if the vessel was allowed 4 days for loading but completed in 3 days, the charterer would receive payment equivalent to half the demurrage rate for that one day saved. This creates a win-win situation: the charterer gets a financial reward, and the shipowner gets their vessel back sooner to start the next voyage.

Types of Laytime Calculation

Now that we understand what laytime means in principle, let’s explore how it’s actually structured in practice. There are several ways it can be structured in charterparties:

1. Fixed laytime: A specific number of hours (e.g., 24, 36, or 48 hours) allowed for loading or discharging.
2. Calculated laytime: Based on a loading/discharging rate (e.g., 1500 metric tons per day). This method ties it directly to the cargo quantity. If a vessel loads 3,000 tons at a rate of 1,500 tons per day, the charterer gets exactly 48 hours (2 days). If they only load 2,250 tons, they get 36 hours.
3. Total time: A combined allocation for both loading and discharging. Instead of separate time allowances for each port, parties agree on one total period covering the entire operation. For example, “72 hours total for loading and discharging combined.” Time used in the loading port reduces the time available for discharge.
4. Per hatch per day: An agreed rate multiplied by the number of workable hatches. Common for larger vessels, this method considers the ship’s configuration. A vessel with 4 hatches at a rate of 500 tons per hatch per day would have an effective loading rate of 2,000 tons per day. This accounts for the practical reality that more hatches generally mean faster cargo operations.

Commencement of Laytime

Before the contractual time for loading or discharge can start running, several specific conditions must be met. These aren’t just formalities; they’re fundamental requirements that courts scrutinise carefully in disputes. The following essential conditions must be satisfied:

1. The vessel must have arrived at the agreed destination
2. The vessel must be ready in all material respects to load or discharge cargo
3. Valid notice of readiness (NOR) has been tendered
4. The specified notice time has elapsed (typically following the “2pm/8am” rule)

The “2pm/8am” rule, commonly found in Gencon charterparties, states that if NOR is tendered before noon, it commences at 2:00 PM the same day; if after noon, it commences at 8:00 AM the next working day. Once these conditions are met, the vessel becomes an “arrived ship” and time for loading or discharge begins to count.

Arrived ship: Port Charter and Berth Charter

The question of when a vessel has “arrived” depends critically on whether you have a port charter or berth charter — a distinction that can make or break a demurrage claim.

Port Charter: The vessel must reach the named port and be at the immediate and effective disposition of the charterer. The concept of an “arrived ship” under port charters was clarified in The Johanna Oldendorff [1973] 2 Lloyd’s Rep 285, where the court established that a ship is an “arrived ship” when it is:

• Within the port limits
• At the immediate and effective disposition of the charterer
• In a position where it is customary for vessels to wait

This could be at the designated berth or, if the berth is occupied, at the usual waiting place within port limits. The key advantage for charterers is that once the vessel meets these criteria and is ready, laytime can commence even if they’re waiting for a berth.

Berth Charter: The vessel is not considered “arrived” until it reaches the specific loading or discharging berth designated by the charterers. Until then, it’s still considered to be on voyage. This places the risk of port congestion on the shipowner rather than the charterer.

However, charterparties often modify these basic rules with clauses commonly known as “Whether” clauses or “W” clauses (sometimes abbreviated as “WWWW” in fixture recaps):

• WIBON (Whether In Berth Or Not): Converts a berth charter into something more like a port charter when the berth is unavailable due to congestion
• WIPON (Whether In Port Or Not): Allows NOR tendering even from outside port limits when congestion prevents waiting within the port
• WIFPON (Whether In Free Pratique Or Not): Allows NOR tendering before health clearance is obtained
• WICCON (Whether In Customs Clearance Or Not): Permits NOR tendering before customs formalities are completed

These clauses effectively transfer various risks from shipowners to charterers by allowing earlier tendering of NOR under specific circumstances.”

The “WWWW” abbreviation in fixture recaps is a shorthand way for brokers and charterers to indicate that all the standard “Whether” clauses apply, making the negotiation process more efficient.

Notice of Readiness (NOR)

The NOR is a formal notification by the master or agent of the vessel to the charterer that the vessel has arrived at the port of loading or discharge and is ready to load or discharge cargo. Under English law, the NOR must be:

• Valid (the vessel must be physically and legally ready)
  • Physical readiness means holds are clean, dry, and fit for the intended cargo, and all relevant equipment (cranes, hatches, pumps) is operational.
  • Legal readiness means all necessary documentation is in order for immediate commencement of cargo operations.
• Given to the proper party
• Given at a permitted time (usually during office hours)
• Not tendered before the agreed laydays (unless specifically permitted)

NOR can be tendered only when the vessel becomes arrived as per the charterparty terms.

In The Mexico I [1990] 1 Lloyd’s Rep 507, the Court of Appeal established the fundamental principle that a notice of readiness must contain accurate statements of fact to be valid. In this case, the vessel tendered NOR on arrival at the discharge port, but the charterers’ cargo was not accessible due to overstowing by completion cargo. The court held that because the vessel was not actually ready to commence discharge operations when the notice was given, the NOR was invalid and a nullity. Crucially, the court ruled that an invalid notice does not subsequently become valid when circumstances change – if there is any doubt about validity, a fresh notice must be tendered.

The case also established that charterers may waive the defect in an invalid notice, but only through clear conduct such as accepting the notice and commencing cargo operations without reservation.

End of laytime

Laytime ends in one of two ways: either the agreed time for loading or discharge expires, or cargo operations are completed within the allowed time. Determining the precise moment when cargo operations are “completed” varies significantly between dry and liquid cargo operations and can be a frequent source of disputes.

For dry cargo vessels, it generally runs until loading is completed and the vessel can proceed on her voyage in safety. This may include completion of loading/discharging, closing hatches, and removal of all dunnage (Gencon 1994 Clause 5: “time to count until dunnage removed“).

For tankers, it usually runs until loading/discharging hoses are disconnected or, in the case of loading, until the relevant cargo documentation has been placed on board.

Courts generally allow 2-3 hours for preparing cargo documents after physical completion. However, excessive delays can result in demurrage claims. The completion time recorded on the Statement of Facts is crucial for laytime calculations.

Laytime Calculation Methods

Laytime can be calculated in various ways depending on the charterparty terms:

1. Running Days/Calendar Days: Continuous count of days including weekends and holidays
2. Working Days: Only counting days when work is normally carried out at the port
3. Weather Working Days: Working days excluding periods when weather prevents cargo operations

These methods determine the basic framework for counting time, but they work in conjunction with various exceptions and inclusions.

Exceptions to Laytime Calculation

Once the basic calculation method is established, charterparties specify which periods are included or excluded from calculations.

Weekend and Holiday Clauses

There are two main abbreviations commonly used in charterparties:

• SHINC (Sundays and Holidays Included): No weekend clause – time counts continuously without interruption
• SHEX (Sundays and Holidays Excluded): Time stops counting during weekends and holidays

Additional abbreviations specify how to count time if work is done during excluded periods:

• UU (Unless Used): Excluded periods don’t count unless used for cargo operations
• ATUTC (Actual Time Used To Count): Only the actual working time during excluded periods counts
• HTUTC (Half Time Used To Count): Half the time worked in excluded periods counts
• EIU (Even If Used): Excluded periods don’t count even if used for cargo operations

For example, “SHEX UU” means Sundays and holidays don’t count unless the vessel actually works during those periods.

Weather Conditions

When evaluating weather exceptions, charterparties typically use one of three main terms:

1. Weather Permitting (WP): Only interruptions for weather DURING cargo operations can be deducted from laytime
2. Weather Working Day (WWD): Similar to WP, but also includes weather that would have prevented working while the vessel was waiting for berth (but only during normal port working hours)
3. Weather Working Day of 24 Consecutive Hours (WWD of 24CH): All weather delays mentioned on the Statement of Facts can be deducted, whether day or night, and whether the vessel is working or waiting

Port Restrictions and Regulations

Local port regulations may affect calculations, such as:

• Prohibitions on night work
• Weekend work restrictions
• Public holidays

Special Clauses and Situations

Charterparties often include specialised clauses addressing particular operational risks or circumstances that can affect vessel performance. These provisions typically allocate specific risks between owners and charterers, modifying the general principles discussed above.

Strike Clause

The Gencon 1994 Charter Party’s Strike Clause (Clause 16) is one of the most intricate provisions in standard charterparties, creating different procedures for loading and discharging ports with strict notification requirements and time limits.

Loading Ports

The clause distinguishes between strikes occurring before loading begins and strikes during loading operations:

• Before loading: Owners may require charterers to agree that laytime counts as if no strike occurred. Charterers must respond within 24 hours, or owners have the right to cancel the charterparty. If charterers refuse to count time, owners may still choose to proceed to the loading port, but time during the strike will not count as laytime.
• During loading: If a strike begins after loading has commenced, the vessel may sail with liberty to complete with other cargo elsewhere.

Discharging Ports

The procedures for discharge differs. Owners must notify charterers of any impending strike. Charterers have 48 hours to respond and must choose to either:

• Keep the vessel waiting at the discharge port (laytime counts as if no strike occurred until it expires, then half demurrage rate until the strike ends, then full rate)
• Order the vessel to an alternative port

Ice Clause

The Ice Clause (e.g. Clause 18 in Gencon 1994 Charter Party) addresses situations where ice may prevent a vessel from reaching a port or creates a risk of the vessel being frozen in. These clauses recognise that ice can create situations where vessels could be damaged beyond normal wear and tear or where crew safety may be compromised.

The fundamental principle is that the master has supreme authority to decide whether to leave a port or not enter a port “for fear of being frozen in.” This decision cannot be questioned at the time it is made and is paramount over commercial considerations.

Loading Ports

The ice clause under Gencon 1994 creates different scenarios depending on when ice becomes a problem:

• Before arrival: If the loading port becomes inaccessible due to ice, owners may cancel the charterparty and declare it “null and void” under Clause 18(a). No consequences arise for either party, and no laytime penalties apply.
• Partial loading: If ice prevents completion of loading, owners have the option to complete with other cargo at ice-free alternative ports under new charterparty terms. The original charter remains valid for cargo already loaded, with freight and laytime calculated pro-rata.

Discharging Ports

For discharge ports, the clause provides more detailed procedures:

• Notice requirement: Owners must give notice to charterers of the port’s inaccessibility due to ice.
• Charterers’ options: Within 48 hours of receiving notice, charterers must choose to either:
  • Keep the vessel waiting on demurrage until the reopening of navigation, or
  • Send the vessel to an alternative safe and accessible port
• The 48-hour period: This time does not count as laytime and is considered “owners’ time.”

Force Majeure

Charterparties may contain other specific provisions dealing with force majeure events.

However, English law does not recognise a general doctrine of force majeure. Unlike in civil law jurisdictions, force majeure only applies in English law if the parties have expressly included such provisions in their contract. Therefore, if a charterparty is silent on force majeure, charterers cannot invoke it as a defence, regardless of how extraordinary the circumstances may be.

On the other hand, English courts will strictly interpret force majeure clauses where they do exist, requiring a direct causal link between the force majeure event and the inability to perform contractual obligations.

Once on Demurrage, Always on Demurrage

This principle, firmly established in English law, means that once a vessel goes on demurrage, it remains in that status until cargo operations are completed, regardless of subsequent events.

Exception clauses (such as bad weather or weekends, strikes and the like) stop working unless they explicitly say they apply to time on demurrage. Ambiguous or general words are insufficient. The leading authority is Union of India v Compania Naviera Aeolus (The Spalmatori) [1962] 2 Lloyd’s Rep 175, where the House of Lords held that strike wording which did not mention demurrage could not stop the clock once the vessel was already on the charge.

The maxim is therefore best read as:

Unless an exceptions clause specifically refers to demurrage, it is effective only while laytime is running

Where the vessel is already on the charge at the loading port, the same clock continues at the discharge port—either from the moment of arrival or after any contractual notice period, depending on the charter wording.

Limitations of the maxim:

• Owner’s own fault. Time lost because of the owner’s breach (e.g. gear failure) is still deducted; the maxim does not excuse culpable delay.
• Express exceptions. If parties draft clear words, those words prevail.

Calculation of Demurrage

The charge is typically:

• Calculated at a daily rate specified in the charterparty
• Continues to accrue until completion of cargo operations
• Payable without proof of actual loss (as liquidated damages)

The rates are usually expressed as a daily amount (e.g., “USD 10,000 per day pro rata”), meaning partial days are calculated proportionally.

Demurrage Claims and Time Bar Clauses

Submitting a successful demurrage claim requires careful preparation and comprehensive documentation. Essential documents typically include:

• Invoice stating the amount claimed;
• Laytime calculation (timesheet) showing how the amount was computed;
• Notice of Readiness demonstrating when the vessel arrived and was ready;
• Statement of Facts providing a chronological record of port events.
• Additional supporting documentation may include correspondence, weather reports, port logs, pumping records for liquid cargo, and protest letters.

it is crucial to pay attention to time bar clauses, which are particularly prevalent in tanker charterparties and often contain extremely strict documentary and timing requirements:

• Typical periods range from 30 to 90 days after completion of discharge
• Claims submitted after the deadline are considered waived
• Complete documentation must be provided within the time limit
• These clauses have been strictly enforced by English courts

English courts interpret time bar clauses with strict literalism, showing little sympathy for technical failures to comply. The commercial rationale, as explained in The Oltenia [1982] 1 Lloyd’s Rep 448, is “to ensure that claims were made by the owners within a short period of final discharge so that the claims could be investigated and if possible resolved while the facts were still fresh.”

Tricon Energy Ltd v MTM Trading LLC [2020] EWHC 700 (Comm) demonstrates how strict courts can be. The shipowners submitted a $56,049 demurrage claim within the 90-day deadline, including detailed calculations, NOR, statement of facts, and protest letters. However, they failed to provide copies of the bills of lading.

The charterparty required the claim to be calculated pro rata to the “bill of lading quantities” and demanded “all supporting documents.” Despite the owners arguing that the statement of facts contained the relevant quantity information, the High Court ruled that the bills of lading were essential supporting documents. The entire claim was time-barred due to this omission.

Mr Justice Robin Knowles emphasised that where a charterparty specifically references “bill of lading quantities” and requires “all supporting documents,” courts will not accept substitutes or duplicative information. The fact that sensitive information could be redacted was considered irrelevant to the obligation to provide the underlying documents.

Many demurrage disputes are referred to arbitration under the London Maritime Arbitrators Association (LMAA) Terms, which serve as the default forum for most charter-party claims and apply the same strict documentary and time-bar requirements discussed above.

The above is only a general overview. For a detailed analysis of the case law, documentary requirements, and whether errors can be corrected after the bar has expired, see the separate article Demurrage Time Bar: How Not to Lose Your Demurrage Claim.

Demurrage as liquidated damages

Demurrage represents liquidated damages – a pre-agreed estimate of the owner’s likely losses from vessel delays. This classification has several important legal consequences.

As liquidated damages, owners need not prove that charterers were at fault for the delay or establish a causal link between charterers’ actions and the vessel’s delay. The charge becomes payable automatically once laytime expires, regardless of why the delay occurred. This differs significantly from unliquidated damages claims, where fault and causation must be established.

However, owners cannot recover this sum for delays caused by their own actions or inaction. For example, if cargo operations are delayed due to vessel equipment failure or crew negligence, this time would typically be deducted from any claim.

Because the agreed rate represents a pre-quantified estimate of the owner’s likely losses, it generally provides the exclusive remedy for such delay. Shipowners cannot normally claim anything above that figure, as doing so would undermine the liquidated-damages principle.

Mitigation of Damages and Demurrage

In general contract law, parties suffering loss have a duty to mitigate their damages – meaning they must take reasonable steps to minimise their losses and cannot recover for losses that could have been reasonably avoided.

However, the position changes once demurrage begins to accrue. Because this sum is a liquidated estimate of the owner’s loss, the owner is not ordinarily required to mitigate after the free-time allowance has expired.

Shipowners must, however, continue to act reasonably. They may not extend the delay or inflate costs through their own conduct; any time lost or expense caused by the owner’s fault will still be deducted.

Detention

Detention represents a form of unliquidated damages that can be claimed when a vessel is delayed but no agreed laytime and demurrage regime applies.

For instance, a vessel is en route to the discharge port but is ordered by charterers to slow down or wait at sea because the discharge port is not ready to receive the cargo due to the charterer’s failure to arrange proper receiving facilities. Since the vessel has not yet arrived at the discharge port, no laytime regime applies, but owners may claim detention for the additional time and fuel costs caused by the charterer’s breach.

Detention requires owners to prove their actual losses and establish that the delay was caused by the charterer’s breach of contract. This makes detention claims more complex and uncertain, as they involve detailed evidence about actual costs incurred and potential earnings lost.

However, it is common for parties to agree that detention shall be payable at the same rate as demurrage, which simplifies the calculation and avoids the burden of proving actual losses.

Container Demurrage and Detention

In container shipping, the application of these terms differ significantly from vessel chartering. The basic principle – a fee for delay – remains unchanged, but the specific conditions and rules for their application vary.

After unloading the container, the customer is obligated to collect the cargo and return the cleaned container within a limited time. This period is called “free time”. Container demurrage is charged for storing the container beyond the set time, while container detention is charged for the late return of the container.

The rates often include a progressive scale: the longer the delay, the higher the daily fee. For example:

• 1-7 days delay: $50 per day
• 8-14 days delay: $75 per day
• 15+ days delay: $100 per day

This incentivises customers to return containers on time to avoid higher charges.

Conclusion

The contractual rules governing a vessel’s free-time allowance and any consequent delay charges are far more than technicalities; they set the economic tempo of every voyage. Errors in their calculation or application can leave owners or charterers facing unexpected, and often sizeable, liabilities. English authority is intricate and each charter form carries its own pitfalls, so early, specialist advice invariably pays for itself.

If you need legal support on charter-party disputes, cargo claims, or arbitration, you are welcome to contact me by e-mail, Telegram, or WhatsApp. I provide legal assistance across the full spectrum of maritime transport and dispute resolution.