Demurrage and detention: what they are, and how to stay clear of both
Two charges that start the day a container's free time runs out — one while the box is still at the port, one after it has left.
First, free time
When a full container is unloaded, it is given a number of days to be collected from the terminal. Once it has been collected, it is given more days for the empty to be returned. These are its free time.
How many days you get depends on the shipping line, the port and your contract, so it can differ from one shipment to the next. Some shipping lines count the two together as one combined free time. Your freight forwarder or the shipping line can tell you the free time for each shipment.
Demurrage: the box is still at the port
If the full container is still inside the terminal when its free time ends, demurrage starts: a charge for every extra day it stays there. The last day you can collect it without paying demurrage is its last free day — the date that matters most once a container has arrived.
Detention: the box is with you
Once you have collected the container, a different clock is running: the one for bringing the empty back. Keep the container past that free time and detention starts — a charge for every extra day the shipping line's equipment is out of its hands. Some lines call it per diem.
The quick way to tell them apart
Ask where the container is.
- Still in the terminal, waiting to be collected: demurrage.
- Out of the terminal, with you or on its way back: detention.
Who sends the bill, and whether the two are charged separately, depends on the shipping line and the port — your contract has the answer.
How to stay clear of both
- Know the last free day the day the container is unloaded. Ask your forwarder or the shipping line, and write it down where everyone who arranges the collection will see it.
- Plan against the latest arrival date, not the booking. Ships arrive late — and sometimes early. Book the truck and the customs paperwork against the newest ETA, and check it again as the ship gets close.
- Have the clearance papers ready before the ship arrives. A box waiting for documents is a box using up its free days.
- Plan the empty's return when you collect it. Know where the empty goes back to and by when, before the truck leaves the port.
- Ask for more free time before you need it. If your containers regularly need longer, it is easier to agree extra days in the contract than to dispute a charge afterwards.
In SailPing: add a container's last free day when it reaches the port, and it is counted down on your dashboard and on the container — and shown in red, at the top of your dashboard and in your notifications, the day it passes.