Glossary term
Demurrage
A charge for keeping equipment or cargo beyond the free time allowed, typically inside a terminal.
A charge that begins when free time expires. In container shipping it generally covers a container held inside the terminal beyond the allowed period; detention covers the container held outside it. In chartering, demurrage is what a charterer pays for exceeding the agreed laytime.
The terms are used inconsistently between carriers and countries, so the definition that matters is the one in the tariff being charged against. Charges accrue daily and escalate, and they are the most common unexpected cost in an import.