Every shipper who has paid a detention invoice they did not expect asks the same question afterwards: at what point did this become unavoidable? The answer is almost always the same, and it is earlier than people think. By the time a container is discharged, most of the exposure is already fixed.
Where the clock actually starts
Detention is counted in calendar days from the moment the free time granted on your bill of lading is exhausted. Not working days. Not from the day you collected the box. The tariff bands escalate, so the cost is not linear — at Jebel Ali the first chargeable period runs at AED 147 a day for a 20ft unit, and by the fourth week the same box is running at AED 520. A ten-day overrun is not twice a five-day overrun; it is closer to three times.
The controllable decisions are all made before the vessel berths. After discharge you are managing consequences, not causes.
The four decisions that set the bill
- Documentation reviewed in advance. A bill of lading that has not been surrendered, a missing certificate, an inconsistent commodity description — each of these stops the box at the gate while the clock runs.
- The slot booked against the discharge date. If the facility is booked for the week after the vessel arrives, the container waits.
- The replacement equipment positioned. On a cross-stuffing job, the outbound container has to be on the ground before the inbound one is opened.
- Transport arranged for the day of release. Not the day after. A single day of drift at the front of the operation is a day at the back of it too.
What good planning is worth
Take a straightforward case: three 40ft containers arriving at Jebel Ali with seven free days, cross stuffed and re-exported.
| Scenario | Days used | Detention (3 × 40ft) |
|---|---|---|
| Planned in advance | 7 | Nil |
| Documents chased after arrival | 12 | AED 5,142 |
| Documents and equipment both late | 19 | AED 17,082 |
The difference between the first and third rows is not operational skill. It is a fortnight of preparation that costs nothing.
Model it before you commit
Our Jebel Ali detention calculator and the BND calculator publish the current bands in full, and the Jebel Ali port storage tariff covers the terminal side. Run the numbers against your own free time before a booking is committed, rather than reading them off an invoice afterwards.
If you would like us to look at a specific movement, send us the details and we will come back with a working view of the exposure.
Published 29 July 2026 · All insights →