Demurrage & detention calculator
Calculate the demurrage or detention charge for a container based on your carrier's free time, tiered daily rates, and the actual number of days. The math is simple — but the tier structure (rates that step up after day 5, day 10, day 15) is the part that catches people out. Bring your own rates from your carrier's tariff sheet; we don't ship default rates because demurrage tariffs change quarterly and stale numbers do more harm than good.
Inputs
Defaults are blank on purpose. Use your carrier's published tariff.
Tariff (tiered daily rate)
Most carriers charge a low rate for days 1–5 past free time, a higher rate for the next block, and a third tier for prolonged delays. Add or remove tiers to match your carrier's tariff exactly.
What is demurrage, and how is it different from detention?
The two terms are routinely conflated, but they refer to different containers in different places under different contracts:
- Demurrage is charged by the terminal (or by the carrier on the terminal's behalf) when a full import container sits at the port for longer than its free time. It compensates the terminal for occupied yard space. Demurrage clocks start when the container is discharged from the vessel and stop when it's picked up by the consignee or trucker.
- Detention is charged by the carrier (the shipping line) when their container leaves the terminal but isn't returned empty within the free time. It compensates the carrier for the equipment being out of circulation. Detention clocks start when the container leaves the terminal gate and stop when it's returned empty to the depot.
- Some carriers publish a combined "merchant haulage" tariff (often called "demurrage & detention combined") where the free time and rates are bundled. Read the tariff carefully — combined free time is usually shorter than the sum of separate dem + det free time.
Why charges escalate fast
Almost every major liner uses a tiered structure that ramps steeply. Maersk, Hapag-Lloyd, MSC, CMA CGM and ONE all publish tariffs of the form: free time → low rate for days 1–5 past free → 2–3× higher for days 6–10 → 3–5× higher for day 11+. A 20' container that sits 14 days past free time can easily cost more than the original ocean freight. Real examples and tariff schedules are published quarterly on each carrier's local websites — Maersk's local-charges pages, Hapag-Lloyd's "demurrage & detention" tariff page, MSC's local-charges tariff PDF — always check the version dated for the country and quarter you're shipping in.
How to avoid these charges
- Pre-alert tracking. Most demurrage is paid because the consignee discovers the container is at the terminal too late. ETAs change; if your operations team is reading them in three different emails per shipment, things slip.
- Documents ready before discharge. If the B/L isn't surrendered or the import declaration isn't ready when the vessel arrives, the container starts accruing demurrage from day one of free time. Booking-email parsing into the TMS is what prevents this.
- Negotiate free time on volume contracts. Standard free time is 4–7 calendar days for demurrage and 3–5 for detention. On annual contracts, asking for 10–14 days free time is reasonable for shippers with large volume; many carriers grant it without raising base freight.
- Empty return planning. Detention charges accrue because empty depots are full or far from the consignee. Build the empty return into the dispatch schedule, not as an afterthought.
Sources: Maersk demurrage and detention tariff pages (per region); Hapag-Lloyd "Charges" → "Demurrage and Detention" pages; MSC local-charges tariff PDFs; Container xChange's annual D&D Benchmark report; FreightWaves / The Loadstar editorial coverage. Cited as guidance only — always use your contract's actual tariff sheet for billing-quality numbers.
Want AI to flag demurrage risk before containers arrive?
Logentic reads booking emails, ETA updates and B/Ls, then alerts your team when free time is about to expire and documents are still missing. Stops most demurrage at the source — the desk, three days earlier.
See track & trace automation →