How to dispute a COSCO demurrage or detention invoice
A practical, step-by-step process for disputing COSCO demurrage & detention (D&D) charges — what evidence to pull, the errors to look for, and how to file so the dispute actually gets paid.
Can you actually win a dispute with COSCO?
Yes — when it's documented. Industry experience since the US Ocean Shipping Reform Act (OSRA 2022) is that roughly 20–30% of demurrage & detention charges are overturned when disputed with evidence. Most invoices are never checked at all, which is why billing errors persist: the sender rarely hears about them.
COSCO, like every major carrier, processes disputes through a formal channel and responds to contract-cited, timestamp-backed recalculations far better than to general complaints. COSCO Shipping Lines handles D&D through local agencies with tariffs published per region; dispute through the contact on the invoice and insist on a written reference for the case.
The five-step dispute process
Pull the evidence before you argue: the invoice, your carrier contract (or the quoted tariff), the bill of lading, and the terminal's own event data — discharge date, gate-out date, empty-return date. The dispute is won or lost on these four documents.
Check the clock, not the charge. Most successful disputes aren't about whether a delay happened — they're about mechanics: demurrage billed from vessel arrival instead of container discharge, detention billed from discharge instead of gate-out, negotiated free time not applied, the wrong tariff tier, weekends or port closures counted against you, or demurrage and detention overlapping the same days.
File inside the window. Invoice terms typically give a short dispute window — often 21–30 days from invoice date — and claims raised after it are routinely refused regardless of merit. Diarise it the day the invoice lands.
Dispute through the carrier's own channel (portal or disputes inbox) in procedural language: cite the invoice number, the contract clause, and the terminal timestamps, and state the corrected calculation. Attach everything. Angry emails lose; documented recalculations win.
Chase to a credit note. A dispute that is 'acknowledged' is not money. Track every case to an issued credit note or corrected invoice, and record the outcome — what worked against this carrier at this port will work again.
The errors to look for first
Wrong clock start (arrival vs discharge for demurrage; discharge vs gate-out for detention) · negotiated free time not applied — the invoice silently uses the standard tariff · wrong rate tier for the day count · charges across weekends, holidays or terminal closures your terms exclude · days when the box could not legally or physically be collected (carrier hold, no appointments) · demurrage and detention double-billed over the same days · invoices missing the OSRA-required fields or issued outside the contractual window — often voidable in full.
On US trades, OSRA requires the invoice to carry thirteen specific data points (dates, free days, rate basis, dispute contact). An invoice missing them is non-compliant — say so in the dispute.
Or let the audit do it
Marevo reads every COSCO invoice against your contract and the terminal timestamps automatically, drafts the dispute with the evidence attached, and tracks it to the credit note. The retro-audit of your last quarter's invoices is free — if your COSCO invoices are clean, you'll have proven it; if they're not, you'll have a number.
Frequently asked
How long do I have to dispute a COSCO D&D invoice?
Check the invoice terms and your contract — dispute windows are commonly 21–30 days from invoice date. Treat the window as a hard deadline: late disputes are routinely refused on timing alone.
What evidence wins a demurrage dispute?
The carrier contract clause granting your free time, the terminal's own event timestamps (discharge, gate-out, empty return), and a corrected day-by-day calculation. Attach all three; cite them by name.
Is disputing worth it for small invoices?
Individually, sometimes not — which is what carriers count on. Audited in bulk, error rates of even 10–20% across a year of invoices add up to real money, and automation removes the hour-per-invoice cost that made checking uneconomic.
Find out what your last quarter owes you
Marevo reads your invoices against your contracts and the terminal data, drafts the disputes, and is paid mostly from what actually comes back. The audit itself is free.
Claim the free audit