Reversible laytime and despatch

The two-port problem

A voyage charter carries cargo from one or more load ports to one or more discharge ports. At each port the charterer is given a fixed slice of laytime , the free time during which the owner keeps the vessel available for cargo work without extra payment. When the charterer beats that allowance the ship is released early; when the charterer runs past it the ship is detained. Demurrage prices the detention, and despatch prices the early release. Both are measured against the same allowance.

That leaves one structural question that has to be answered before any money can be worked out. Are the load and the discharge accounts kept apart, or are they added together? Two charters that both grant ninety-six hours of total laytime can arrange that time in ways that produce different bills:

1. Split, or non-reversible. Forty-eight hours at the load port and forty-eight at the discharge port, each calculated on its own. Despatch is earned where time is saved; demurrage is owed where time is exceeded; the two figures are netted at the end.
2. Reversible. Forty-eight plus forty-eight treated as a single ninety-six-hour pool, measured against the total time actually used across both ports. One calculation, one result.
3. Averaged. Separate calculations at each port, with an explicit instruction to set the saving in one operation against the excess in the other.

The three sound close, and drafters often blur them, but they are defined terms with defined effects. Getting the choice wrong, or leaving it unstated, is one of the more expensive slips in a voyage fixture, because it changes who pays whom and how much.

Reversible laytime under the 2013 definitions

The authoritative statement of what these words mean is the Laytime Definitions for Charter Parties 2013, produced jointly by BIMCO, the Comite Maritime International, FONASBA and the Baltic Exchange, and published in September 2013 to replace the 1993 Voyage Charter Party Laytime Interpretation Rules (Voylayrules). The definitions carry weight only when a charter party expressly incorporates them, which many modern recap-driven fixtures now do, and they are drafted to reflect the current state of English law.

Definition 24 sets out reversible laytime in full:

REVERSIBLE LAYTIME shall mean an option given to the charterer to add together the time allowed for loading and discharging. Where the option is exercised the effect is the same as a total time being specified to cover both operations.

Two features of that wording repay attention. The first is the word option. Reversibility is framed as a right the charterer may exercise, not an automatic pooling that happens by itself. Some fixtures do make it automatic and unconditional, but the standard language is elective, and a few charters require the charterer to declare the election, sometimes before the vessel sails from the load port. Read the clause and find the trigger.

The second is the phrase the same as a total time being specified. Once the option bites, the two separate allowances collapse into a single figure, and the calculation runs against the sum of the time used at every relevant port. The charterer’s benefit is plain: a quick load buys extra time for a slow discharge, and demurrage arises only when the aggregate is overspent. Owners accept the arrangement when they can trade it for a tighter total allowance or a firmer demurrage rate, since the pooling removes the per-port demurrage they might otherwise have collected.

Averaging is not the same as reversible

Practitioners frequently use “averaged” and “reversible” as if they were interchangeable. The 2013 definitions treat them as separate ideas, and the distinction is worth holding onto. Definition 23 reads:

TO AVERAGE LAYTIME shall mean that separate calculations are to be made for loading and discharging and that any time saved in one operation is to be set off against any excess time used in the other.

Set the two side by side. Averaging keeps the load and discharge sums separate, produces a saving or an excess at each, and then sets one against the other. Reversibility adds the allowances together first and runs a single calculation against a single pool. In most ordinary voyages the net money lands in the same place, because both methods let a saving at one port cancel an overrun at the other. The mechanism still differs, and that difference surfaces whenever another clause attaches to one operation on its own. A weather exclusion, a shifting-time provision, or a port-specific exception applies to a discrete per-port calculation under averaging, whereas under true reversibility there is arguably one merged account for those adjustments to work on. Careful drafters pick one word deliberately rather than treating the pair as synonyms.

The default when the charter is silent

If the charter party says nothing about combining the two operations, the position is non-reversible, split laytime. Each port stands as its own commercial event, and the law does not read in a pooling that the parties did not write. A charterer who wants reversibility has to negotiate it in, either with the word “reversible” or by stating a single total allowance that covers both loading and discharging.

The practical consequence runs both ways. A charterer who forgets to ask for reversibility can find, after the event, that a comfortable saving at the load port earns only half-rate despatch while a modest overrun at the discharge port attracts full-rate demurrage, so the two do not cancel. An owner who concedes reversibility without lifting the rate can find that demurrage which would have been payable on a split basis simply evaporates into the pool. Neither outcome is a surprise if the clause is read at the fixing stage; both are a surprise if the point is left to the laytime accountants months later.

How the combined calculation works

Under reversible laytime the arithmetic is mechanical once each port’s used figure is known:

1. Compute the time used at the load port from the statement of facts , applying the charter’s SHEX or SHINC treatment and any weather exclusions.
2. Compute the time used at the discharge port in the same way.
3. Add the two used figures to get combined time used.
4. Add the two allowed figures to get combined time allowed.
5. If combined used exceeds combined allowed, demurrage runs on the excess.
6. If combined used is less than combined allowed, despatch runs on the saving.

The net position is the difference between the two totals:

The subtlety is not the addition. It is that each per-port used figure is itself the product of the charter’s ordinary exclusions, and those exclusions can differ between load and discharge: different SHEX days, different weather conventions, different shifting and warping rules. Reversibility pools the net used time at each port, never the raw elapsed time. Compute each port properly first, then combine.

SHEX and SHINC, worth a word here, are the common abbreviations for Sundays and Holidays Excepted and Sundays and Holidays Included. They are trade shorthand rather than numbered entries in the 2013 definitions, which instead define the underlying ideas, such as the weather working day in Definition 15 and excepted or excluded time in Definition 19. The charter states which regime applies, and the time sheet gives effect to it.

How exclusions shape the used figure

The used figure at each port is not raw elapsed time; it is elapsed time with the charter’s exclusions taken out. A weather working day, Definition 15, counts only to the extent that weather would have allowed cargo work, and the definition prorates the exclusion by the ratio the interruption bears to the time that could have been worked. So rain that halts a grain load for four hours out of a notional eight-hour working stretch removes a proportion of the day from laytime, not the whole day. SHEX takes out Sundays and holidays; a “weather permitting” qualifier takes out weather stoppages; a shifting clause may put berth-to-berth moves outside laytime. Each exclusion enlarges time saved, so each one feeds straight into despatch, and each one is a place a despatch claim can be attacked or defended.

That is why reversibility pools the net figures. Two ports can run different exclusion regimes: a SHEX load port and a SHINC discharge port, or different weather conventions at each. Reversibility does not merge the regimes; it computes each port under its own rules, then adds the results. Merge the exclusions by mistake and the combined figure is wrong.

A worked comparison: reversible versus split

Take a single charter fixed two ways. Sixty hours allowed at the load port, sixty at the discharge port, so one hundred and twenty hours combined. Demurrage is USD 30,000 per day; despatch is half demurrage, USD 15,000 per day, on an all-working-time-saved basis. Suppose the load port uses forty hours (a saving of twenty) and the discharge port uses ninety hours (an overrun of thirty).

On a non-reversible basis the two ports are settled separately:

• Load port saving: 20 hours, or $20/24 = 0.833$ days, at USD 15,000 gives USD 12,500 despatch to the charterer.
• Discharge port overrun: 30 hours, or $30/24 = 1.25$ days, at USD 30,000 gives USD 37,500 demurrage to the owner.
• Net: the charterer pays the owner $37{,}500 - 12{,}500 =$ USD 25,000.

On a reversible basis the ports are pooled first:

• Combined used: $40 + 90 = 130$ hours. Combined allowed: 120 hours. Excess: 10 hours, or $10/24 = 0.417$ days.
• Demurrage on the excess: $0.417 \times 30{,}000 =$ USD 12,500 to the owner. No despatch arises.

Same voyage, same rates, same facts: USD 25,000 under split, USD 12,500 under reversible. The gap is not a rounding artefact. Under the split account the twenty hours saved at the load port are only ever worth despatch at the half rate, while the thirty hours lost at discharge cost demurrage at the full rate. Reversibility lets those saved hours offset the lost hours one for one, in effect crediting the saving at the full demurrage rate. That is the structural reason reversible laytime tends to favour the charterer whenever port performance is uneven, and it is why owners price the concession.

When both ports finish early, or both run late, the two methods converge, because there is no offset to capture. They diverge precisely when one port is in despatch and the other in demurrage.

A two-load, one-discharge illustration

Reversibility across several ports pools every call. Take two load ports and one discharge port, allowances of 30, 30 and 60 hours, so 120 hours combined, reversible across all three. Demurrage USD 36,000 per day; despatch half demurrage, USD 18,000 per day, AWTS. Suppose the first load port uses 22 hours, the second 41 hours, and the discharge port 45 hours.

• Combined used: $22 + 41 + 45 = 108$ hours. Combined allowed: 120 hours. Saving: 12 hours, or 0.5 days.
• Despatch: $0.5 \times 18{,}000 =$ USD 9,000 to the charterer.

Run the same facts split, port by port: the first load port saves 8 hours, the second exceeds by 11 hours, the discharge saves 15 hours. At the AWTS half rate the two savings earn $8/24 \times 18{,}000 = 6{,}000$ and $15/24 \times 18{,}000 = 11{,}250$, a total of USD 17,250 despatch, against $11/24 \times 36{,}000 = 16{,}500$ demurrage, for a net USD 750 despatch. Combined despatch of USD 9,000 against split despatch of USD 750: same facts, an USD 8,250 swing, and this time the pooled result favours the charterer by more, because the single overrun is diluted across three ports’ worth of allowance. The direction of the swing depends on the pattern of savings and overruns, which is why the reversibility choice is negotiated rather than assumed.

Multiple load or discharge ports

Many fixtures call at two or more load ports, or two or more discharge ports. Reversibility then needs a defined scope. It can pool across every port called; across all load ports or all discharge ports but not between the two classes; or within each load-and-discharge pair. A clause that says only “laytime reversible” without fixing the scope invites argument, and any genuine ambiguity may be construed against the party who put the clause forward. Say which ports are pooled.

The statement of facts is unchanged

The choice between reversible and split does not touch the statement of facts . That document stays a per-port record, signed at each port as events happen. The reversibility convention lives in the laytime statement that the claims department builds afterwards, not in the field record. The master at the load port has no reason to think about reversibility when signing; the master and the agent record the facts truthfully, and the accountants apply the charter’s rules downstream. A clean statement of facts protects both sides whichever laytime basis governs.

Despatch: the reverse of demurrage

Despatch is the reward to the charterer for finishing cargo work inside the allowed laytime. Definition 31 of the 2013 rules puts it plainly:

DESPATCH MONEY or DESPATCH shall mean an agreed amount payable by the owner if the Vessel completes loading or discharging before the Laytime has expired.

In economic terms it is the mirror of demurrage. Demurrage compensates the owner for time taken beyond the allowance; despatch compensates the charterer for time given back inside it. Together they align the parties’ incentives, since the charterer wants a fast turn and the owner wants the ship back at sea. The despatch spelling is the maritime term of art; “dispatch” is the ordinary US spelling of the same word and means exactly the same thing here.

Despatch is not universal. Many tanker and large-volume dry-cargo charters carry demurrage but no despatch, leaving the owner the whole upside of a quick operation. Plenty of smaller dry-bulk and break-bulk fixtures, particularly in Atlantic Basin and Mediterranean trades, do pay it.

Why despatch belongs to dry cargo

Despatch grew up in the dry-bulk and general-cargo trades, and its home is the FIO fixture, free in and out, where the charterer takes on loading and discharging and hires the stevedores. Because the charterer controls the cargo operation, it makes commercial sense to reward the charterer for doing it quickly and to charge the charterer when it drags. The owner’s exposure is symmetrical: demurrage if the charterer is slow, despatch if the charterer is fast.

Tankers sit on the other side of that line. In the oil trade the terminal, not the charterer, usually controls the pumps and the shore tanks, and the cargo moves fast once connected, so the custom never developed of paying the charterer for a quick turn. The standard tanker forms therefore carry demurrage without a despatch counterpart, and an owner keeps the full benefit of a fast discharge. The rule of thumb, dry cargo pays despatch and tankers do not, reflects who runs the cargo operation and who bears its cost.

Despatch, demurrage and detention

Three related payments need keeping apart. Demurrage is the agreed daily sum the charterer pays for keeping the vessel past the laytime, and it is liquidated damages, a fixed rate that saves the owner from proving actual loss. Despatch is its mirror, the sum the owner pays for time given back. Detention is different again: it is unliquidated damages at large, payable when the vessel is delayed by the charterer in circumstances the demurrage clause does not cover, or after any agreed demurrage period has run out, and the owner must prove the loss. Despatch never turns into detention; it is a bonus, not a liability, and it stops at zero when time saved reaches zero.

The despatch rate

The rate is normally pinned to the demurrage rate:

• Despatch half demurrage (DHD). Despatch rate equals half the demurrage rate. By a wide margin the most common convention worldwide.
• Despatch one-third demurrage. Seen in some grain trades.
• Free despatch. None payable; the owner keeps the upside. Standard in tanker trades and many big dry-bulk fixtures, and usually written as “fd” after the demurrage rate.
• Despatch equal to demurrage. Rare, and generally a symptom of a soft market where the charterer holds the bargaining power.

The half-demurrage default reflects a rough fairness. The charterer captures half the value of the time saved, on the footing that the owner did part of the work that made the saving possible through vessel speed, pumping rate or gear. Expressed as a formula, on the half-demurrage basis:

where $R_{\text{dem}}$ is the daily demurrage rate and $t_{\text{saved}}$ is the time saved in days on the agreed basis.

Time saved: ATS versus AWTS

The most consequential despatch choice is how the saving is measured, and the 2013 definitions give the two standard answers exact wording.

Definition 32, all working time saved, also called all laytime saved:

DESPATCH ON ALL WORKING TIME SAVED or ON ALL LAYTIME SAVED shall mean that Despatch Money shall be payable for the time from the completion of loading or discharging until the expiry of the Laytime excluding any periods excepted from the Laytime.

Definition 33, all time saved:

DESPATCH ON ALL TIME SAVED shall mean that Despatch Money shall be payable for the time from the completion of loading or discharging to the expiry of the Laytime including periods excepted from the Laytime.

The single difference is the treatment of excepted periods. AWTS strips Sundays, holidays and weather out of the saving, so despatch is paid on counted laytime only. ATS leaves them in, so despatch is paid on the full elapsed calendar saving to the ship. Where a voyage crosses excepted time the two answers part company, and the gap is one full day of despatch for every excepted day inside the window.

A worked comparison: ATS versus AWTS

Ninety-six hours allowed at the discharge port. Demurrage USD 24,000 per day; despatch half demurrage, USD 12,000 per day. Notice of Readiness tendered Friday 06:00, laytime commencing Friday 18:00 after the notice period. Discharge completes Monday 06:00. The charter is SHEX, so Sunday does not count as laytime.

• Elapsed time, Friday 18:00 to Monday 06:00: 60 hours.
• Sunday excepted, 00:00 to 24:00: 24 hours.
• Counted laytime used: $60 - 24 =$ 36 hours.

Now measure the saving each way:

• AWTS: allowed minus counted used, $96 - 36 = 60$ hours, or 2.5 days. Despatch $= 2.5 \times 12{,}000 =$ USD 30,000.
• ATS: allowed minus elapsed, $96 - 60 = 36$ hours, or 1.5 days. Despatch $= 1.5 \times 12{,}000 =$ USD 18,000.

AWTS pays USD 12,000 more, which is exactly one excepted Sunday at the despatch rate. Stretch the voyage across two weekends, or add a public holiday, and the divergence widens by another day each time. This is why a despatch clause that reads only “despatch half demurrage” without naming ATS or AWTS is an unfinished clause: the parties have agreed the rate and left the larger variable open. Where the drafting is silent and English law governs, the received view is that a bare reference to time saved points toward the all-time-saved measure, calculated as demurrage would be, without regard to the laytime exceptions. That is a default worth displacing expressly if the charterer intends AWTS.

Despatch on a reversible charter

Despatch on a reversible charter runs on the combined saving, not on per-port savings:

1. Compute combined time used, per the reversible method above.
2. Compute combined time allowed.
3. If used is less than allowed, the difference is the saving.
4. Apply the ATS or AWTS convention as drafted.
5. Multiply the saving in days by the despatch rate.

Reversible despatch is generally smaller than the sum of per-port despatch on a split charter, because a saving at one port cannot become despatch if an overrun at the other absorbs it. From the charterer’s chair that is the cost of the demurrage protection: less upside in exchange for less downside. The two features are two halves of the same bargain.

Once on demurrage, always on demurrage

Reversibility and despatch both sit on top of the laytime account, and the laytime account is governed by a rule that surprises charterers more than any other. Once laytime has run out and the vessel is on demurrage, the exceptions that used to stop the laytime clock no longer stop the demurrage clock. Demurrage keeps accruing through Sundays, holidays and weather unless the charter party clearly says those exceptions extend to demurrage as well.

The 2013 definition of demurrage now codifies the point. Definition 30 reads:

DEMURRAGE shall mean an agreed amount payable to the owner in respect of delay to the Vessel once the Laytime has expired, for which the owner is not responsible. Demurrage shall not be subject to exceptions which apply to Laytime unless specifically stated in the Charter Party.

That second sentence is the “once on demurrage, always on demurrage” maxim reduced to a defined term. The rule has deep roots in English case law. In Union of India v Compania Naviera Aeolus SA (The Spalmatori) [1964] AC 868 the House of Lords, in the speech of Lord Reid, treated as correct the proposition that once a vessel is on demurrage no exception will operate to interrupt the demurrage unless the clause is clearly worded to that effect. The underlying logic reaches back to William Alexander & Sons v Aktieselskabet Dampskibet Hansa [1920] AC 88, where the charterer’s undertaking to load or discharge within the fixed time was held to be, in substance, an absolute one, answerable for delay whatever its cause, save for the owner’s fault or an exception clearly written into the charter.

The reasoning is causal. Demurrage is liquidated damages for the charterer’s breach in overrunning the laytime. Had the charterer performed on time, the later stoppage would have found the ship already gone, so a stoppage arising after laytime has expired falls on the charterer who is already in breach. The one exception that applies even without express words is delay caused by the owner or those for whom the owner is responsible, since the charterer cannot be charged demurrage for the owner’s own failure to keep the ship ready and working.

For the reversible and despatch analysis the rule cuts in a specific direction. The exceptions that shrink counted laytime, and so enlarge despatch, do their work only up to the moment laytime expires. Cross that line and the same Sunday or weather stoppage that would have been free during laytime becomes chargeable demurrage. A charterer relying on excepted time to build a despatch cushion needs to keep the operation inside the allowance; the cushion vanishes the instant the ship tips into demurrage, and clear contrary wording is the only thing that preserves it.

Despatch across the standard forms

How the leading forms treat despatch is a function of trade, and the split between dry cargo and tankers is sharp.

GENCON. The printed GENCON 1994 form deals with demurrage alone. Clause 7 makes demurrage payable at the rate and in the manner stated in Box 20, day by day; there is no despatch clause in the standard text. Despatch is added by the parties when they want it, most often as a note in Box 20 or through a rider that overrides the printed clause under the Part I over Part II priority rule. Where no despatch is agreed, Box 20 is marked “free despatch” or “fd” alongside the demurrage figure. GENCON 2022, the centenary revision, keeps the same architecture: a demurrage regime in the form, with despatch a matter for the parties to add. Reversibility likewise is not built into the printed GENCON laytime mechanism and is inserted through the laytime box or a rider when required.

ASBATANKVOY. The standard tanker voyage form provides for demurrage and no despatch. Charterers pay demurrage per running hour, and pro rata, for all time that used laytime exceeds the allowed laytime, with the rate halved in the specific circumstances the clause lists, such as fire, explosion, storm, strike or breakdown of machinery at the charterer’s, shipper’s or receiver’s facility. There is no despatch counterpart. An owner on a tanker fixture keeps the whole value of a fast turn.

SHELLVOY 6 and BPVOY. The Shell and BP voyage forms follow the tanker pattern: demurrage yes, despatch no. Despatch simply is not part of standard tanker terms, and a tanker fixture that pays it does so only by special agreement bolted onto the form.

The takeaway is a rule of thumb worth stating cleanly. Dry-cargo voyage charters commonly pay despatch, usually at half demurrage; tanker voyage charters usually do not. Neither of the two tanker forms named here has a dedicated wiki page; where a form needs a home in the internal mesh, the voyage charter party article gives the general framework that all of them share.

Notice of Readiness, commencement, and the account

Everything above sits on the moment laytime starts, and that moment turns on the Notice of Readiness . Definition 25 of the 2013 rules describes the notice as the notification, to the charterer or other named party, that the vessel has arrived at the port or berth and is ready to load or discharge. A valid notice, tendered as the charter requires, starts the laytime clock, usually after any stated notice period or turn-time. An invalid notice does not start it, and the lost hours pile onto the used side of the account.

Three conditions have to line up before laytime can start. The vessel must be an arrived ship, meaning she has reached the agreed destination, a berth under a berth charter or the port under a port charter; she must be ready in fact and in law to work the cargo, holds clean or tanks ready; and a valid notice must have been given. Where the berth is not free on arrival, a “whether in berth or not” provision, Definition 27, lets the vessel tender notice from the usual waiting place, so the waiting time counts. The tanker forms differ on this: ASBATANKVOY and BPVOY are port charters where notice can be tendered on arrival at the port, while the older SHELLVOY 5 was a berth charter. Free pratique and customs clearance are usually treated as formalities that do not delay a notice unless the charter makes them conditions. Each of these feeds the commencement time, the commencement time feeds time used, and time used drives despatch.

The despatch consequence is direct. A late or defective notice increases time used and cuts time saved, so it shrinks despatch or grows demurrage at that port. On a reversible charter the damage is not confined to the port where the notice failed: because the account is pooled, a bad notice at the load port can swallow despatch that the charterer earned by a brisk discharge, and the reverse. Masters should tender clean, valid notices everywhere on a reversible voyage, because the financial reach of an error is wider than it looks.

The statement of facts and the time sheet

The evidence that drives any laytime, despatch or demurrage figure is the statement of facts and the time sheet built from it. The statement of facts is the chronological field record, signed at each port by the master and the agent, capturing arrival, notice tender, the notice period, commencement, each cargo operation and every stoppage with its cause. The time sheet is the accountant’s working: it takes those raw events, applies the charter’s exceptions, and produces time used, time allowed, and the balance that becomes despatch or demurrage.

For despatch specifically the record has to support the excepted periods that the charterer wants credited under AWTS, and it has to justify the commencement time that flows from the notice. Disputes on despatch, like disputes on demurrage, usually come down to a handful of recurring issues: whether a claimed stoppage was truly outside laytime, whether the notice was valid, whether the drafting points to ATS or AWTS, and whether the claim was brought in time. A well-kept statement of facts settles most of them before they become arguments.

Invoicing, time bars and documentation

The despatch claim is the charterer’s to bring, since the owner is the payer. After the laytime account is agreed, the charterer prepares a despatch invoice and sends it to the owner. A sound invoice shows time used and time allowed at each port, the combined figures if the charter is reversible, the time saved on the stated basis, the despatch rate, the total, and the statement of facts and supporting papers as backup. The owner’s claims team then pays or disputes.

Time bars matter here as much as they do for demurrage. Many charters set a documented deadline, often sixty or ninety days from completion of discharge, within which demurrage and despatch claims must be submitted in full. A charterer who misses the bar, or serves an invoice without the supporting documents the clause demands, can lose the whole claim on merit-blind grounds. The deadline should be diarised from the date of completion and the invoice sent, fully papered, well before it expires. Despatch is litigated less often than demurrage, mostly because the sums are smaller, the half rate applied to a usually smaller saving, but the governing principles and the same case law apply to both.

Common drafting pitfalls

Silence. The commonest failure is a clause that does not choose. “Laytime 96 hours total” that omits reversible or split, or “despatch half demurrage” that omits ATS or AWTS, leaves both parties exposed to a default one of them will not like. Draft reversibility and the despatch basis as express, separate lines: the laytime allowance and whether it is reversible; the despatch rate and whether it is on all time saved or all working time saved; the demurrage rate; and the claims time bar.

Blurring averaging and reversibility. Because the two produce the same net money on an ordinary voyage, drafters treat them as one. They are defined differently, and the difference tells when a port-specific exception or shifting clause attaches to one operation only. Pick the word that matches the intended mechanism.

Notice of Readiness on reversible voyages. A defective notice at one port propagates into the combined account and can erase despatch earned elsewhere. The amplified effect is a reason for extra care with notices whenever the charter is reversible.

Scope of reversibility over many ports. “Laytime reversible” without saying which ports are pooled is ambiguous and may be read against the drafter. State the scope: all ports, load ports only, discharge ports only, or per pair.

Currency and rounding. Despatch rates are stated per day in the charter’s currency, and cents count on large claims. Use the same rounding the demurrage calculation uses, and settle currency conversion, where the charter is quoted in one currency but paid in another, by the date the charter specifies.

Assuming exceptions survive into demurrage. They do not, absent clear words. A charterer who lets the operation slip past the allowance loses the benefit of the SHEX Sundays and weather stoppages that a despatch calculation would have credited, because the vessel is now on demurrage and the exceptions no longer bite. Plan the operation, and the clause, around that rule.

Despatch in voyage economics

Despatch is one line in the charterer’s voyage estimate , and rarely the largest, but it shapes vessel selection at the margin. A charterer choosing between two ships may take the nominally dearer one if its faster pumps or better gear reliably turn into despatch, since the despatch recovered across a year of fixtures adds up for a large operator. The saving is money the charterer books, not a rebate on freight.

For the owner despatch is part of the vessel’s commercial reputation. A ship that consistently finishes inside laytime is easy to fix and earns a small premium in a firm market; one that habitually runs into demurrage is fixed at a discount or passed over. The owner manages despatch and demurrage together as a single performance signal, alongside speed and consumption, and prices reversibility into the rate when a charterer asks for it. On a reversible fixture the owner is in effect selling the charterer an option to net the ports, and an option has a price.

Limitations

This article states the general English-law position and the standard-form practice; it is not a substitute for reading the fixture. A charter party can define its own laytime terms, exclude or amend the 2013 definitions, set an idiosyncratic despatch basis, or attach a bespoke time bar, and the specific wording controls over any general rule described here. Governing law also matters: a charter under New York law or another system may resolve a silent despatch basis differently from English law. Where a live dispute turns on the exact meaning of a clause, the primary sources cited below and qualified legal advice on the actual contract wording are the proper references.

Related Articles

• Laytime : the free time the whole account is measured against.
• Demurrage : the commercial mirror of despatch.
• Notice of Readiness : the event that starts the laytime clock.
• Statement of facts : the evidentiary basis for every figure.
• Voyage charter party : the contract that houses the laytime, despatch and demurrage terms.
• GENCON charter party : the standard dry-cargo voyage form and its Box 20 demurrage regime.
• Charter parties overview : where voyage, time and bareboat charters sit relative to one another.
• Voyage estimation : how despatch and demurrage feed the voyage profit and loss.