Freight D&D Auditor · Guide
Last free day calculator
The last free day (LFD) is the final day you can pick up a container (or return an empty) before demurrage or detention starts accruing. Carriers sometimes print an LFD earlier than the availability date plus contractual free time implies — this calculator shows what the clock should say under the operating-day convention.
Regulatory content verified against the sources below on 2026-07-02.
Demurrage: container availability date. Detention: gate-out date.
From your service contract or the carrier's tariff.
Weekends + US federal holidays applied.
Assumes free time does not consume weekends or observed US federal holidays. Whether that's true for your shipment depends on your tariff or service contract — some grant calendar-day free time. Always check your contract terms; this tool illustrates the operating-day convention only.
How the LFD is determined
Free time starts when the container becomes available for retrieval (for demurrage at the terminal) or when you gate the container out (for detention / per-diem on the equipment). How many free days you get — and whether they're counted as calendar days or terminal operating days — comes from your service contract or the carrier's tariff, not from any regulation. The FMC billing rule does require every invoice to state the allowed free time, its start and end dates, and (for imports) the container availability date (46 CFR § 541.6(b)), which is exactly what makes the printed LFD checkable.
When the printed LFD doesn't match
Two common causes: the carrier's availability date is earlier than when the container was actually retrievable (it was still on the vessel, unstacked, or on customs hold with no gate appointment available), or free time was counted through days the terminal wasn't operating. Both are worth disputing in writing with dates and evidence — see our dispute letter template and the invoice requirements checklist. The FMC's interpretive rule (46 CFR § 545.5) directs the Commission to consider whether charges relate to actual cargo availability when assessing whether a demurrage practice is reasonable.
Primary sources
- 46 CFR Part 541 — Demurrage and Detention (eCFR, current text)
- 46 CFR § 545.5 — FMC interpretive rule on demurrage & detention (eCFR)
Regulations change. Always check the current text at the links above — they go to the official electronic Code of Federal Regulations, not a summary.
Check your invoice in about a minute
Our audit recomputes the free-time math on your D&D invoice with deterministic date logic and checks it against the FMC's minimum invoice content. The audit is free and doesn't require an account.
Run a free audit →This page is general information about published regulations, not legal advice, and doesn't account for the terms of your tariff, service contract, or negotiated arrangement, which govern your specific charges. No outcome is guaranteed or implied. For advice about your situation, consult a licensed attorney or licensed customs broker.