What is the difference between demurrage, detention and storage?
In common container-shipping usage, demurrage applies when carrier equipment stays inside a terminal beyond allowed free time, while detention applies when the equipment is outside the terminal and is not returned within the allowed period. Port, terminal or CFS storage is a separate charge for occupying space. Definitions, start points and billing parties vary, so the applicable quotation, tariff and arrival notice control the actual calculation.
Charge comparison
| Charge | Typical trigger | Container or cargo location | Common billing party |
|---|---|---|---|
| Demurrage | Carrier equipment remains at the terminal beyond carrier free time. | Inside port or terminal. | Shipping line or equipment provider. |
| Detention | Equipment remains with the merchant outside the terminal beyond allowed time. | Outside terminal, often at consignee or shipper premises. | Shipping line or equipment provider. |
| Port/CFS storage | Cargo or container occupies facility space beyond facility free time. | Port, terminal, CFS, ICD or warehouse. | Facility, terminal or its operator. |
A shipment can incur more than one charge during the same delay because the equipment owner and the facility operator provide different assets. Do not assume a carrier free-time approval automatically changes terminal storage rules.
How container free time works
Free time is the allowed period before a particular time-based charge begins. It can be expressed as separate demurrage and detention periods or as a combined period. The clock may use calendar days, working days or another tariff definition. Start points can relate to discharge, availability, gate-out, empty pickup, terminal gate-in or another documented milestone.
Daily rates often increase in slabs. A delay that moves from the first slab to a later slab can therefore cost more per day. Check whether tax, currency conversion, administration or facility charges apply in addition to the base tariff.
Where import and export delays occur
Discharge to empty return
- Original or electronic cargo release is incomplete.
- Customs filing, assessment, examination or duty payment is delayed.
- Delivery order, terminal payment or transporter planning is pending.
- Consignee warehouse is not ready to unload.
- Empty-return depot changes or has restricted slots.
Empty pickup to vessel loading
- Equipment is collected too early before cargo readiness.
- Stuffing, customs or documentation misses the cut-off.
- Container reaches the terminal outside the accepted gate window.
- Vessel rollover changes the operating plan.
- Shipper holds equipment while awaiting buyer instructions.
Exporters should align empty pickup with stuffing and terminal cut-off. Importers should begin documentation, customs and delivery planning before arrival—not after free time has started running.
Seven ways to reduce delay charges
Record free time in the booking file
Capture the written terms, tariff basis and responsible party instead of relying on a verbal estimate.
Pre-check documents
Resolve Bill of Lading, invoice, packing list, licence and customs-data differences before arrival or cut-off.
Plan customs early
Share classification, valuation and supporting documents with the authorised customs team in advance.
Reserve transport and unloading
Confirm vehicle, driver, terminal slot, warehouse labour and equipment needed to unload the cargo.
Track release milestones separately
Monitor carrier release, customs release, terminal payment and physical delivery as separate dependencies.
Return empties immediately
Obtain the current return depot and acceptance status, then retain the equipment interchange or gate receipt.
Escalate before expiry
If a documented event prevents movement, request instructions or an extension before free time expires and preserve evidence.
Demurrage and detention FAQs
What is the difference between demurrage and detention?
Demurrage commonly concerns carrier equipment inside the terminal; detention commonly concerns equipment outside the terminal before empty return. Check the applicable tariff definition.
Is port storage the same as demurrage?
No. Storage is generally charged by the facility for space, while demurrage is generally an equipment charge. Both may apply.
Are free days always calendar days?
No. The quotation or tariff may define calendar days, working days, holidays and the clock's start point differently.
Can more free time be requested?
Sometimes, depending on the route, carrier and commercial terms. Negotiate before booking and obtain written confirmation.
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