Demurrage and detention explained

Demurrage vs detention - the difference

People use the two words interchangeably, but they cover different stages - and the distinction matters when you are checking a bill.

• Demurrage accrues while your container is still inside the port or terminal beyond the free time - for imports, after it is discharged from the vessel but before you collect it.
• Detention accrues once you have taken the container out of the terminal (gate-out) but have not returned it empty to the carrier's nominated depot within the free time.

A simple way to remember it: demurrage = container still at the port; detention = container out with you. A single late shipment can rack up both in sequence.

How the charges accrue

Carriers grant a set number of free days - typically 3-7 days for demurrage and 4-7 days for detention, depending on the carrier, port and lane. Once the free time runs out, charges are billed per container, per day, and the daily rate usually escalates the longer you hold the box - the first tier may be modest, but later tiers can be several times higher. On many lanes demurrage alone runs roughly $75-$300 per container per day, and a stuck high-value container can cost more.

One 2026 change worth knowing: the US Federal Maritime Commission's billing rule is now fully in force, so carriers must issue demurrage and detention invoices within 30 days of the charge and include specific supporting detail - which makes disputing an incorrect charge far more practical than it used to be.

Why importers get caught out

These charges almost always come from a timing problem, not bad luck. The usual culprits:

• Customs holds - the entry is not filed or cleared before free time expires (a missing document or unpaid duty stalls release).
• No haulage booked - clearance is done but no truck is arranged to collect the box in time.
• Port congestion - terminals or chassis are backed up and the container cannot move.
• Slow empty return - the box is unpacked but sits at your yard past the detention free time.

Because the clock starts the moment the container is available, problems that look small - a wrong HS code, a delayed payment - turn into daily penalties fast.

How to avoid demurrage and detention

The fix is preparation, not luck:

• Pre-clear customs. Have your customs entry and documents ready before the vessel arrives so the container is released on day one - formal US entries also need a customs bond in place.
• Book haulage in advance so a truck is ready the moment the box clears.
• Know your free time for each shipment and work backwards from the expiry date.
• Unpack and return empties promptly to stop detention.
• Negotiate longer free time upfront on regular lanes - it is often easier than disputing charges later.

These costs are also why we quote on a fully landed-cost basis and flag tight free-time windows before they become charges - see our fees and surcharges guide for the rest of the line items.

How Baobab keeps your containers moving

We coordinate clearance, duty and haulage so they line up with the container's free time, not after it. One coordinator watches each shipment's milestones, pre-files the customs entry, books collection ahead of release, and warns you early if a box is at risk of accruing charges. When demurrage or detention is billed in error, the new 30-day invoicing rules give us a clear basis to challenge it on your behalf.