Can demurrage and detention be charged at the same time?

They generally apply to different periods — demurrage inside the terminal, detention outside it — but overlapping charges can appear when combined tariffs or merged free-time rules are used. Always request a day-by-day accrual breakdown before paying.

How can I dispute a demurrage invoice?

Document appointment attempts, terminal closures, chassis unavailability, and customs hold dates. Under U.S. detention and demurrage billing rules, invoices must contain specific information and charges must be tied to conditions the shipper could actually control.

What is a reasonable amount of free time to negotiate?

Importers with steady volume commonly negotiate 5 to 7 free days on detention in their ocean contracts. Demurrage free time is set by the terminal tariff and is much harder to change.

Does per diem apply to the chassis as well as the container?

Yes, when the chassis is supplied by the carrier or a pool. Chassis per diem accrues independently and often continues after the container is returned if the chassis is not.

Freight & Transportation

Demurrage vs Detention: What They Are and How to Avoid Them

Two charges that look alike on an invoice, come from different parties, and require completely different fixes.

The short answer

Demurrage is charged by the marine terminal when a container stays inside the terminal beyond its free time. Detention is charged by the ocean carrier when you keep their container or chassis outside the terminal beyond free days. Demurrage is a gate problem; detention is a return problem.

The precise distinction

Demurrage accrues while the container is still inside the terminal after the last free day. The terminal is charging you for occupying its yard space. The remedy is to get the container out — which requires customs release, carrier release, an appointment, a chassis, and a truck.

Detention accrues once the container is outside the gate and you are holding the ocean carrier’s equipment beyond the allowed days. The remedy is to strip and return the box. On the domestic trucking side, detention has a second meaning: driver waiting time at your dock beyond a free window, usually two hours.

Typical free time and rate structures

Import demurrage free time: commonly 3–5 calendar days at the terminal, sometimes fewer during congestion.
Detention free days: often 4–5 days on the container after gate-out, negotiable in service contracts.
Charges escalate in tiers — the per-day rate typically doubles or triples after the first few days.
Chassis per diem accrues separately from container per diem and is frequently missed in cost forecasts.
Trucking detention: usually billed hourly after a one- to two-hour free window at pickup or delivery.

Root causes, honestly assessed

The most common cause is not port congestion. It is document and release timing: an ISF filed late, a customs exam, an unpaid freight invoice holding the carrier release, or missing a terminal appointment window by hours.

The second cause is receiving capacity. Warehouses that schedule to average volume rather than vessel arrival patterns generate predictable spikes of unstrippable containers. The third is equipment — chassis shortages and dislocations that no amount of planning at your desk can fix in the moment.

Controls that actually reduce the charges

Track last free day at container level with automated alerts, not spreadsheets refreshed daily.
Clear customs before vessel arrival wherever the entry type allows it.
Pre-book appointments as soon as the container is available; treat appointment capture rate as a KPI.
Pre-pull to a nearby yard when receiving is backed up — yard storage is usually far cheaper than tier-two demurrage.
Negotiate extended free time in ocean service contracts for high-volume lanes.
Dispute charges caused by terminal unavailability; U.S. regulations require charges to be reasonable and incentive-based, and well-documented disputes are frequently reduced.
On the domestic side, publish accurate dock appointment windows and measure trailer turn times to cut driver detention.

Frequently asked questions

Can demurrage and detention be charged at the same time?: They generally apply to different periods — demurrage inside the terminal, detention outside it — but overlapping charges can appear when combined tariffs or merged free-time rules are used. Always request a day-by-day accrual breakdown before paying.
How can I dispute a demurrage invoice?: Document appointment attempts, terminal closures, chassis unavailability, and customs hold dates. Under U.S. detention and demurrage billing rules, invoices must contain specific information and charges must be tied to conditions the shipper could actually control.
What is a reasonable amount of free time to negotiate?: Importers with steady volume commonly negotiate 5 to 7 free days on detention in their ocean contracts. Demurrage free time is set by the terminal tariff and is much harder to change.
Does per diem apply to the chassis as well as the container?: Yes, when the chassis is supplied by the carrier or a pool. Chassis per diem accrues independently and often continues after the container is returned if the chassis is not.