Demurrage vs Detention: What Container Importers Actually Pay For

Demurrage and detention are both time-based container charges, but they usually apply to different parts of the container journey. Importers who treat them as one generic fee can miss the operational cause of the cost.

Demurrage

Maersk defines demurrage as compensation when the carrier’s container remains inside the terminal, port or depot beyond the agreed free time. For imports, that generally means the container has arrived but has not been removed from the terminal in time.

Detention

Detention applies when the carrier’s container is held outside the terminal, port or depot beyond free time. An importer may therefore avoid terminal demurrage by picking up the container but still incur detention if the empty equipment is returned late.

Free time is the key variable

Free time is the agreed period during which these time-based charges do not apply. Rules, calendars and rates vary by carrier, port, contract, country and booking type.

Why delays happen

Customs holds, port congestion, appointment shortages, trucking capacity and communication failures can all contribute. Maersk specifically notes that detention often results from unclear handoffs around when an empty container is ready to return.

Plan before arrival

Container economics should include more than ocean freight. Track ETA, customs readiness, delivery appointment, unloading capacity, empty-return location and last free day. Use the Container Loading Calculator to plan utilization and the Freight Cost Per Unit Calculator to spread accessorial costs across inventory.

For definitions and current carrier terms, see Maersk’s Detention and Demurrage Terms. Rates are local and change over time, so never assume one global free-time rule.