Demurrage vs Detention in Shipping: The Difference and How to Avoid Both

Demurrage and detention sound similar and are often confused, but they are charged for different reasons. Both are time-based penalties tied to containers or cargo, and both can add up quickly if a shipment stalls at the destination. Knowing which is which helps you avoid surprise invoices.

Demurrage applies when your cargo or container stays inside the port or terminal beyond the free time allowed after arrival. It is essentially a charge for occupying the terminal's space too long, usually because customs clearance or pickup is delayed. The clock starts once the free period ends.

Detention, by contrast, applies once you have taken a container out of the terminal but have not returned the empty box to the carrier within the agreed window. It compensates the carrier for the container being kept out of circulation. With RoRo there is no container to return, so detention rarely applies, but demurrage-style storage at the port still can.

To avoid both, prepare your customs documents in advance, line up a customs broker before the vessel arrives, and arrange prompt pickup and container return. Confirm how many free days you have at the destination, since these vary by port and carrier. When in doubt, ask your forwarder for the exact cut-off dates.