Demurrage invoice meaning, and the field to check first
A demurrage invoice is the terminal's or carrier's bill for the days a container stayed inside the port past its free time. It should name the container and bill of lading, the day free time started and ended, the daily rate per tier, the days billed and where to dispute. The field most often wrong is the start date: free time runs from discharge, and invoices sometimes count from arrival.
- Demurrage Invoice
- The invoice a terminal or ocean carrier issues for the days a container remained inside the port beyond its free time, stating the container and bill of lading references, the free-time period, the daily rate applied and the number of days charged.
A demurrage invoice bills you for days. That is all it is: a number of days multiplied by a rate, for a container that stayed inside the terminal past its free time. Which means every argument about it is an argument about the dates, and every one of those dates is on the invoice or should be.
Most people pay it without reading it, because it arrives weeks after the shipment closed and looks like a fait accompli. It is worth ten minutes.
The fields, and what each one is doing
| Field | What it should say | What to check it against |
|---|---|---|
| Container number | The box the charge is for, one line per container | Your own shipment record; consolidated invoices mix boxes with different dates |
| Bill of lading | The B/L the container moved on | The B/L itself, not the booking |
| Free time start | The date free time began, which is discharge from the vessel | The terminal’s discharge record. This is the field that is wrong most often |
| Free time allowance | The number of free days applied | Your service contract, not the carrier’s default tariff |
| Last free day | Start plus allowance, on the counting basis your tariff sets | Recompute it. Calendar days and working days give different answers |
| Days charged, by tier | Demurrage usually steps up, so days sit in bands | The tariff’s tier table for that port and equipment |
| Daily rate per tier | The rate applied in each band | Your contract rate, which may not be the published one |
| Total | The arithmetic | Do it yourself. Tier boundaries are a common error |
| Dispute route and deadline | Where to contest it and by when | The rules of the trade it moved in |
Start with the start date
Free time runs from discharge from the vessel. Not from arrival at the anchorage, not from berthing, not from the day the arrival notice was emailed to a mailbox nobody reads.
Those events can be days apart on a congested call, and an invoice that starts the clock at the wrong one bills days you never owed. Because the last free day is derived from the start date, and the tier bands are derived from the last free day, a two-day error at the top can move the total by more than two days’ worth: it can push days into a higher band.
Check that one field first, every time.
Then check the allowance against your own contract
The second common error is the carrier applying its published tariff allowance when you negotiated a longer one. Free time is not a standard number. It varies by carrier, port, terminal, direction and equipment, and it varies by what you agreed. If your service contract gives you seven days on a lane and the invoice applied five, two days have been billed at the top tier.
This is only checkable if somebody on your desk holds the free-time terms per lane and per carrier. Most desks do not, which is the real reason these invoices get paid unread.
What the rules require it to contain
In US trades, quite a lot. The Federal Maritime Commission’s billing rule at 46 CFR part 541 makes the invoice content mandatory, requires the invoice to be issued within 30 calendar days of the date the charge last accrued, and provides that where it is not, the billed party is not required to pay. It also sets minimum dispute windows of at least 30 days each way.
One caution, because pages written in 2024 still get this wrong: the section of that rule which limited who could be invoiced, 46 CFR 541.4, was set aside by the D.C. Circuit in September 2025 and removed from the regulation in January 2026. The content and timing requirements are untouched.
Outside US trades there is no equivalent. What the invoice must contain is whatever the carrier’s tariff and your contract say, which in practice means you have less to point at and more need for your own dated record.
If the days were not yours
Some periods are recoverable and most are not. Days Customs held the consignment can be covered in India by a detention certificate against the custodian’s charge. Days the terminal was shut or the carrier could not release the box are arguable. Days lost because a supplier had not sent the invoice are yours, and no rule covers them.
The full order of work, per jurisdiction, is in the walkthrough on contesting the charge once the bill has landed.
The invoice you never receive
The cheapest demurrage invoice is the one that was never raised, and the whole of that outcome is decided in the weeks before the vessel discharges. On an ordinary import desk the document pack runs about eight days behind free time, and a week of demurrage on one container has cost US$12,000 on a reported incident.
Reading the invoice well recovers a fraction of that. Finishing the pack inside free time recovers the rest, which is what software that counts back from the last free day is for.
Questions traders ask
What is a demurrage invoice?
The terminal's or carrier's bill for the days a container sat inside the port past its free time. It is a storage charge, billed per container per day, and it is separate from the detention invoice you may also receive from the shipping line for the same box after it left the gate.
What should a demurrage invoice contain?
Enough to check it: the container number and the bill of lading it moved on, the date free time started and the date it ended, the free-time allowance applied, the daily rate for each tier and the days charged in each, the total, and where and by when to dispute. For shipments in US trades the Federal Maritime Commission's billing rule makes that content mandatory and requires the invoice within 30 calendar days of the charge last accruing.
Which field on a demurrage invoice is most often wrong?
The start date. Free time runs from discharge from the vessel, and an invoice that counts from vessel arrival, from berthing or from the arrival notice will bill days you do not owe. Check it against the discharge date on the terminal's own record before anything else, because every downstream figure is derived from it.
Why did I get a demurrage invoice and a detention invoice for the same container?
Because they are two charges on two clocks. Demurrage covers the box sitting inside the terminal past free time; detention covers the carrier's equipment being out after the box left the gate and before the empty came back. One late document pack commonly triggers both, and they can come from different parties.
How long do I have to dispute a demurrage invoice?
In US trades the FMC billing rule gives the billed party at least 30 days to request mitigation, refund or waiver and the billing party at least 30 days to answer, with longer periods allowed by agreement. Outside those trades there is no statutory clock and your contract and the line's tariff decide, which usually means a short one. Read the invoice the day it arrives.
Sources
- US Federal Maritime Commission, Demurrage and Detention Billing Requirements final rule, 46 CFR part 541 (published 26 February 2024, effective 28 May 2024) · checked 2026-09-07
- World Shipping Council v. Federal Maritime Commission, US Court of Appeals for the D.C. Circuit, 23 September 2025: 46 CFR 541.4 set aside; the Commission removed the section by final rule in January 2026 · checked 2026-09-07
- US Federal Maritime Commission, Interpretive Rule on Demurrage and Detention (46 CFR § 545.5) · checked 2026-09-07
- Docket operational baseline, import–export desk · checked 2026-09-07