The container left your factory on Tuesday and was gated in on Wednesday, comfortably inside the free time you were told about. Six weeks later an invoice arrives for eleven days of demurrage on that same box.
Nothing went wrong at your end. The ship did.
Demurrage and detention are the only charges in an export where the meter is running on equipment you no longer have, at a place you cannot enter, driven by events you were not told about. That is why they are argued about more than any other line on a freight bill, and why almost every argument is lost.
The reason the argument is lost is that it is usually the wrong argument. Exporters dispute the rate. The rate is published and it is not going to move. What decides the size of the bill is which clock was running, when it started, and what stops it.
There are three clocks, and only one of them measures your yard
The word "demurrage" gets used for all of it. It is three different charges measuring three different things, and they are billed under different rules.
| The charge | What it measures | Where the box is |
|---|---|---|
| Detention | You are holding the line's container outside the terminal, port or depot beyond free time | Your factory, your yard, on a truck |
| Demurrage | You are holding the line's container inside the terminal, port or depot beyond free time | Stacked at the port, waiting for a ship |
| Storage | Use of the port, terminal or depot facility itself beyond free time | The same stack, billed by whoever owns the ground |
Only the first one is about you. Detention is the clock that runs while the box sits at your factory being packed, and it is the only one your own operation controls end to end.
Demurrage is the one that produces surprise invoices, because on an export it runs after you have finished. The box is in the terminal. You cannot touch it, move it, or make the ship leave sooner.
Some carriers merge the two into a single combined clock covering the whole period from empty pick-up to loading. That sounds like a simplification. It is not, as the next section shows.
The export clock starts when you take the empty box, not when you load it
Set out end to end, an export runs through the clocks like this:
- You pull an empty container from the depot. Detention starts that day, and the day of pick-up counts.
- You pack it and send it to the terminal. Detention stops on the day it is gated in, and that day counts too.
- Demurrage starts on the same gate-in day, and that day counts again.
- The ship sails. Demurrage stops.
Two things in that sequence catch people out.
The gate-in day sits inside both clocks. One carrier's Thailand terms say detention ends on and includes the day the full container is gated in, and demurrage commences on and includes that same day. It is one day of physical time and two days of billing.
Nothing in step 4 is yours. One global carrier's Thailand tariff ends export demurrage on the day of the vessel's actual departure. Another ends it at the first ETD with confirmed open gate status published on its own e-service site.
Read those two side by side, because on a delayed sailing they produce different bills from the same facts. Measured to actual departure, a ship that leaves four days late adds four days to your clock. Measured to the first ETD, it does not.
That is the single biggest difference between two carriers on the same lane, it is worth more than most rate negotiations, and it appears nowhere in a freight quotation.
Free time is not a market number, and the spread is enormous
There is no standard. Three carriers publishing current tariffs for the same Thai ports do not agree on how many days you get, on whether the days are separate or shared, or on whether weekends count.
| Carrier tariff | Export free time, dry container | How it is counted |
|---|---|---|
| One major global line | 6 days demurrage and 6 days detention, priced at zero, billing starts on day 7 of each | Two separate clocks |
| One major global line | 7 days demurrage and 7 days detention | Calendar days, explicitly including Saturdays, Sundays and public holidays |
| A Thailand-based regional line | 5 days, then charging from day 6 | Stated on the tariff as combined free time |
Look at what that table actually says. The counted allowance across three published tariffs for the same lane runs from five days to fourteen. Not five to seven. Five to fourteen, because two of the three give you two clocks and the third gives you one.
That is the trap in combined free time. Five combined days is not slightly less than six plus six. It is the whole export, from empty pick-up to loading, inside a single five-day budget.
Three more things in those tariffs change the number without changing the headline:
Calendar days, not working days. One tariff spells it out: the free days include Saturdays, Sundays and public holidays. Gate in on the Thursday before Songkran and the free time you were quoted is largely spent on days when nothing at the terminal was going to move anyway.
Dangerous goods get less. The Thai regional line's tariff gives normal general purpose and high cube containers five free days of demurrage, and dangerous goods two. Same lane, same port, same box size, less than half the allowance.
Reefers get less and cost far more. On one tariff, export demurrage free time drops from seven days to five for a reefer. On another, a 20 foot reefer runs 2,000 baht a day where a normal 20 foot runs 600, rising to 3,000 against 1,200. A temperature-controlled export that overruns by a week is not a rounding error on the bill.
Gating in at an inland depot spends free time on the carrier's own leg
This is the part that matters most to anyone shipping out of Bangkok, and it is almost never explained at booking.
Export demurrage starts at gate-in to the agreed terminal, port or depot. It stops when the ship leaves. So if you gate in at Lat Krabang ICD rather than at Laem Chabang, your demurrage clock starts at Lat Krabang and does not stop until the vessel sails from Laem Chabang, roughly 90 km away. The rail or road move between the two, which is the carrier's own inland leg, happens inside your free time.
Both of the tariffs that name inland facilities treat them this way. The Thai regional line's sheet lists Bangkok, Laem Chabang and Lat Krabang under one set of numbers and adds that the tariff also applies for local ICD and CFS. The global line's import note counts free time from the last full container gate-in at an ICD or barge terminal, on the same principle in reverse.
For a Bangkok exporter this is not an optional route. One carrier's Thailand page states plainly that there is no CY acceptance at Klong Toey for export and that Bangkok-area cargo should use Lat Krabang ICD, 25 km from central Bangkok and 90 km from Laem Chabang. If your free time budget assumed the clock started at the port, it was wrong by however long the inland leg and the terminal wait take.
The same page carries a second inland-depot detail worth knowing before you plan a heavy load: at Lat Krabang ICD that carrier accepts 27 tonnes in a 20 foot dry container and 26 in a 40 foot, where at Laem Chabang the limit is the container's own payload. A load planned to the port limit may not gate in at the depot at all, which turns into a re-plan, a second truck movement, and days off the clock. Weight and free time look like unrelated problems until the day they are the same problem.
Two mechanisms that make the bill bigger than the days suggest
The frozen ETD. One carrier's Thailand page states that export demurrage and detention are calculated on the ETD prevailing two days before the empty container was picked up. So the arithmetic is anchored to a schedule as it looked before you started packing. If the sailing then moves, the calculation does not follow the ship. Pulling an empty early, against a schedule that later slips, is a decision that costs money in a way nobody flags at the time.
The jump tariff. Every one of these tariffs is tiered: cheap for the first few chargeable days, then two or three steps upward. One carrier's note says that where free time is exceeded, or where a rate agreement or service contract exception applies, billing is not calculated from the first tier, and a jump tariff applies instead.
That has a direct consequence for anything you negotiate. Winning seven extra free days does not restart the price ladder at the bottom. It postpones the start of charging while the ladder keeps climbing behind it, so the first day you do pay can be a middle-tier or top-tier day. On one export tariff the top tier is more than two and a half times the first: 1,550 baht against 600 for a 20 foot dry box, and 2,200 against 900 for a 40 foot.
The practical version: extra free days and a lower daily rate are not the same purchase, and the extra days are worth less than they look. If your overruns tend to be long ones, the tier structure is the thing to negotiate. If they are short and frequent, the free days are.
Why the invoice sticks to you even when it is not your cargo any more
This is the part that catches exporters who sold on terms where the buyer was supposed to handle everything from the port onward.
Under a standard bill of lading, "Merchant" is not one company. One widely used set of terms defines it to include the shipper, the holder of the bill, the consignee, the receiver, anyone owning or entitled to possess the goods or the bill, and anyone acting on their behalf. A later clause then makes every person inside that definition, including their principals, jointly and severally liable to the carrier for everything the Merchant owes.
Jointly and severally means the carrier does not have to work out who caused it. It can invoice whichever Merchant is easiest to collect from, in full. If your buyer in the destination country leaves a box on the quay for a month, you are inside the definition of Merchant on that bill of lading.
A further clause closes the obvious escape. Where the carrier has accepted instructions to collect freight, duties, fees and demurrage or detention from the shipper, the consignee or anyone else, and that party does not pay when due, the Merchant remains responsible on evidence of demand. "Freight collect" is a billing instruction, not a transfer of liability.
Three more clauses in the same terms are worth reading once, because they decide what happens after a bill goes unpaid:
- The container is at your risk from the moment you take it. Containers released to the Merchant for packing are at the Merchant's sole risk until redelivered, with an indemnity for loss, damage, delay and third-party claims arising from your use of them.
- The lien is wide and it survives. The carrier has a lien over the goods and the documents for all sums payable, extending to sums due under other contracts unrelated to that shipment, exercisable at any time and place, with a power to sell by public auction or private treaty without notice, and it survives delivery of the goods.
- Unclaimed cargo becomes a disposal problem, not a storage problem. If the goods are unclaimed within a reasonable time, or in the carrier's opinion likely to incur charges beyond their value, the carrier may sell, abandon or dispose of them without notice, at the Merchant's risk and expense, and apply the proceeds against what is owed. Storage ashore after a failure to take delivery counts as due delivery, which ends the carrier's responsibility for the goods while the costs keep running.
The published tariff is not a separate document you never signed, either. The bill of lading incorporates the carrier's tariff by reference and expressly draws attention to the terms on free storage time and container demurrage and detention. The numbers are part of the contract whether or not anyone opened the page.
Where you would have to fight it, if you wanted to
Worth knowing before deciding whether a disputed invoice is worth the argument.
One major carrier's bill of lading applies English law and gives the English High Court exclusive jurisdiction, to the exclusion of the courts of any other country, with US shipments going to US law and a New York federal court instead. Then it adds that the carrier may, at its sole option, bring proceedings against the Merchant at a competent court where the Merchant has a place of business.
That is deliberately one-way. To sue them, you go to London. To sue you, they come to Bangkok.
The carrier's separate demurrage and detention terms do the same thing from the other end: they follow the law and jurisdiction of the contract of carriage, and the carrier may instead opt for the law of your principal place of business, or arbitration under it.
None of this is unusual or hidden. It is simply the reason that the useful work on demurrage happens before the booking, not after the invoice. This is a commercial argument with a carrier, not a legal one in a Thai court.
Get the numbers out of your own carrier before the next booking
Everything above is published. None of it is normally volunteered. Ask for these seven, in writing, alongside the rate:
- Demurrage free days, detention free days, and whether they are separate or combined. The single most valuable question, and the one that separates five days from fourteen.
- Calendar days or working days, and what happens to a public holiday.
- What stops the demurrage clock: the vessel's actual departure, or the ETD as at some earlier date. Ask them to state which, because it is the difference between a delayed ship being your problem and theirs.
- Which ETD the calculation uses, if the sailing moves after you pick up the empty.
- The full tier ladder, not the first tier. Ask what day 12 and day 30 cost, not just day 7.
- Whether your free time starts at the ICD or at the port, if you are gating in inland.
- The reefer and dangerous goods numbers separately, if you ship either. They are not the headline numbers.
Then price the exposure the same way you would price any other exclusion in a freight quote: at the frequency you actually trigger it. Two carriers quoting within 3% of each other on ocean freight are not close if one gives five combined free days and the other gives fourteen and you overrun four times a year.
What to change on Monday
- Pull your last twenty export bookings and measure two intervals: empty pick-up to gate-in, and gate-in to actual sailing. The first is your operation. The second is not, and if it is regularly long, your free time is being spent on the second half.
- Stop pulling empties early "to be safe". Every day the empty sits at your factory is a detention day spent, and on a combined-free-time tariff it comes straight out of the days you will need at the port.
- Check whether you gate in at an ICD. If you do, add the inland leg to your free time arithmetic, because the tariff already has.
- Get the tier ladder before negotiating free days. If your overruns are long, the tiers are worth more than the days.
- Look at the free days for reefers and dangerous goods separately, because they are shorter and the daily rate is several times higher.
- Read the Merchant clause on the bill of lading you actually use. If you sell on terms where the buyer pays destination charges, you are still inside that definition, and joint and several liability means a buyer who abandons a box abroad is your invoice.
- Watch the calendar. Free time counted in calendar days across Songkran or New Year is worth a fraction of the same free time in an ordinary week. Plan the gate-in the same way you would plan a truck booking around a closed window.
- When the invoice does arrive, check the arithmetic before the rate. Look at the dates, whether the gate-in day was billed twice, which tier was applied on the first chargeable day, and what the clock was measured to. That is where the errors are.
Free time is the only allowance in an export that you are given, cannot see being spent, and are billed for afterwards. Find out how many days you actually have, and which of them belong to somebody else's ship.