Detention vs demurrage is the most commonly confused charge pair in container shipping. Demurrage is billed while a loaded container sits inside the terminal past its free time. Detention is billed while the carrier's equipment is outside the terminal, in the shipper's or trucker's hands, past its free time.
Both are per-diem charges, both run on clocks that start at specific gate events, and both usually land on an invoice weeks after the move. That gap is why they fill freight inboxes: the shipper sees two similar line items, cannot tell which clock ran or why, and emails the broker or forwarder who now has to reconstruct the timeline from terminal records.
The approach that fails here is the KB-only bot that pastes the textbook distinction and stops. The customer asking about a demurrage line does not need a definition, they need to know which clock ran on their container, from which event, and for how many days. A definitional answer without the shipment record attached just generates the follow-up email, plus a dispute.
Detention vs demurrage at a glance
| Dimension | Demurrage | Detention |
|---|---|---|
| Where the container is | inside the terminal or port | outside the terminal, with the shipper, consignee, or trucker |
| What is being charged | terminal time for a loaded container past free days | use of the carrier's equipment past free days |
| When the clock starts | at discharge from the vessel (imports) | at gate-out, when the container leaves the terminal |
| When the clock stops | at gate-out pickup | when the empty container is returned |
| Who typically bills it | the ocean carrier or the terminal | the ocean carrier, as equipment owner |
Aide, the agentic AI platform for customer experience, answers charge-confusion threads with the shipment record open: it classifies the question as a detention or demurrage intent, reads the gate events and free-time terms, and replies with which clock ran, from which event, and for how long. Every automated reply is logged for review, and anything contesting the charge routes to a human. See Aide for logistics and freight for how this runs on a live freight desk.
Frequently asked questions
- Is driver detention the same as container detention?
- No. In trucking, detention usually means a carrier charging a shipper or consignee for a driver held at the dock past the free window. Container detention is a per-diem equipment charge from the ocean carrier. Same word, different clock, different biller.
- Can you be charged detention and demurrage on the same container?
- Yes. A container that waits inside the terminal past its free days accrues demurrage, and if it is then held outside past its equipment free time it accrues detention as well. The two clocks run on different segments of the same move.