Two charges quietly drain more money from importers than almost anything else in shipping: demurrage and detention. The good news? They are almost entirely avoidable once you understand how the clock works.
Demurrage vs Detention
- Demurrage is charged when your full container sits inside the port/terminal beyond the allowed free days, waiting to be picked up.
- Detention is charged when you keep the carrier's container outside the terminal (at your warehouse) too long after pickup, before returning the empty.
Simple memory aid: demurrage = container still at the port; detention = container away from the port.
How Free Time Is Counted
Carriers grant a number of free days (often 3–7, depending on the lane and contract). The clock typically starts when the container is discharged/available and stops when it is picked up (demurrage) or returned empty (detention). Charges then accrue per container per day — and usually escalate: the rate per day rises the longer you hold it.
Seven Ways to Stop the Clock
- Pre-clear customs before the vessel arrives — file documents early.
- Have funds ready for duty, VAT and charges so payment is not the bottleneck.
- Book transport to collect the container the moment it is available.
- Negotiate extra free days in your contract for lanes you know are slow.
- Return empties promptly — and get a receipt with the date/time.
- Watch for holidays and congestion that compress your usable free time.
- Track milestones so nothing sits unnoticed.
If You Are Charged Anyway
Ask for the detailed calculation: free days granted, start/stop dates, daily rate. Errors are common. If a delay was caused by the carrier or terminal (e.g. a customs hold not your fault, or no empty-return slots), you may have grounds to dispute or waive part of the charge.
Sources & Further Reading
- Carrier tariff and demurrage/detention schedules (per shipping line).
- UNCTAD and industry commentary on demurrage & detention practices.
- Your contract of carriage / service contract free-time terms.
