How to request a demurrage waiver under the FMC billing rule

This guide takes for granted that the rule covers your invoice (who issued it and what it charges for are in Demurrage vs detention) and that you have held the invoice against the items of section 541.6 (the table is in What a demurrage or detention invoice must contain). The text is 46 CFR part 541 as eCFR shows it, up to date as of October 28, 2026.

Section 541.8 has two paragraphs, and both are about time (46 CFR 541.8). Paragraph (a) says the billing party "must allow the billed party at least thirty (30) calendar days from the invoice issuance date to request mitigation, refund, or waiver of fees from the billing party" (46 CFR 541.8(a)). Paragraph (b) says that on receiving a request the billing party "must attempt to resolve the request within thirty (30) calendar days of receiving such a request or at a later date as agreed upon by both parties" (46 CFR 541.8(b)).

The rule names three kinds of request, mitigation, refund and waiver, and defines none of them: the definitions of 46 CFR 541.3 are of other terms. In ordinary words they are a smaller charge, money paid back and no charge. Say in your request which one you ask for and on what amount. The letter that DemurrageCheck prepares asks for a waiver.

The decision is the billing party's. It must attempt to resolve the request (46 CFR 541.8(b)); that is not a promise to grant it, and DemurrageCheck cannot promise that a carrier will accept a finding, cancel a charge or reduce it. Section 541.8 says nothing about paying the invoice while a request is open: whether and what to pay is for you and your adviser.

Before you write, read the invoice for the three items of 46 CFR 541.6(d). They tell you where the request goes, what to send with it and which time limits the billing party states.

The page behind the address is the one the rule describes: it must give "a detailed description of information or documentation that the billed party must provide to successfully request fee mitigation, refund, or waiver" (46 CFR 541.6(d)(2)). Send what it describes, to the contact on the invoice. If an item is not on the invoice, the request can say so. In our sample report, invoice EX-20413 has no web address for dispute requirements, and the letter for it lists the item as missing. The invoices of the sample are invented: see the sample report.

The time to ask is counted from the invoice issuance date (46 CFR 541.8(a)), not from the day the invoice reached you. The invoice has to state it: 46 CFR 541.6(d)(3) asks for "Defined timeframes that comply with the billing practices in this part", one for your request and one for the answer.

Counting the closing day as inside the window is the product's reading of "at least thirty (30) calendar days from the invoice issuance date", and a reading of the rule is for you and your adviser to confirm. An invoice that states fewer than thirty days is reported as a defect (46 CFR 541.8(a)), and the product counts thirty days for it.

In our sample report, invoice EX-20413 is dated 2026-09-21 and its window closes on 2026-10-21. Invoice EX-20414 is dated 2026-09-22 and states 14 days, so its window is counted as thirty days and closes on 2026-10-22. They are invented invoices: see the sample report. The sample is read as of 2026-10-01.

Section 541.8 sets no content for a request (46 CFR 541.8), so this is how the letter that DemurrageCheck prepares is built and why each part is there. It is one way to write a request, not a form that the rule or the FMC prescribes. The words in the second column are the letter's.

The letter changes with the invoice. When the invoice was issued after the time limit of 46 CFR 541.7, the sentence of 541.5 gives way to "Under 46 CFR 541.7, a billed party is not required to pay a charge invoiced after that period.", and an invoice with both kinds of defect gets both sentences. When the defects are on some of the containers and not on the invoice as a whole, the letter asks about those containers and their amount. A defect on the arithmetic alone gets no letter: the product shows the arithmetic, and a request on that ground is yours to write.

1. Check that the invoice is one the rule covers and that it is billed to your company: the letter goes out in the name of your company.
2. Hold the invoice against the items of 46 CFR 541.6 and write down each item that is not on it, with its paragraph, after looking at every page and attachment.
3. Find the contact, the web address and the time limits that the invoice states, and read the page behind the address.
4. Count the window from the invoice date and send the request before it closes.
5. Say which of the three you ask for, and for what amount. If the defects are on some of the containers, ask about those containers.
6. Send the request to the contact on the invoice, from your company, with what the page describes, and record the date you sent it: the answer date follows from it.
7. When the billing party answers, record what it answered. If the answer date passes in silence, the next step is yours.

• It prepares a letter for an invoice that fails an item of 46 CFR 541.6 or a time limit (checks A1 to A8, listed on the how it works page). For a finding on the arithmetic alone it prepares none.
• It holds the letter back when the invoice names a payer that is not your company, until you confirm the payer, and when a whole-invoice request covers a line whose container number is not confirmed, until you name it.
• It fills in what it read from the invoice. A value it does not have is a bracket, for example [invoice number], and you complete it before you send. If the window is closed or unknown, it leaves out the sentence about the period allowed; if it is closed, it also says that you decide whether to send.
• It does not send the letter and does not contact the billing party. You send the letter from your company and your mailbox, and then record the date you sent it and the answer: cancelled, reduced, refused or no answer.
• It emails reminders for an invoice with a finding, unless you switch them off for your company: 7 days and 2 days before the window closes while no sent letter is recorded, and a reminder when no outcome is recorded and more than 30 days have passed since the date you recorded for sending the request (how it works).
• It cannot promise that a carrier will cancel or reduce a charge. The billing party decides; the rule's words on its answer are in 46 CFR 541.8(b).

• 46 CFR part 541 (eCFR): The text of part 541 as eCFR shows it, up to date as of October 28, 2026
• 46 CFR 541.3, definitions (eCFR): The definitions of part 541, which do not define mitigation, refund or waiver
• 46 CFR 541.5, failure to include required information (eCFR): The consequence of leaving out required information
• 46 CFR 541.6, contents of invoice (eCFR): The dispute information on an invoice (541.6(d)), the identifying information (541.6(a)) and the statements of the billing party (541.6(e))
• 46 CFR 541.7, issuance of invoices (eCFR): The time limit for issuing an invoice, the ground of a letter about a late invoice
• 46 CFR 541.8, requests for fee mitigation, refund, or waiver (eCFR): The time to ask for mitigation, refund, or waiver and the time to attempt to resolve the request
• DemurrageCheck, sample report: The letter for invoice EX-20413 and the windows of invoices EX-20413 and EX-20414 (invented invoices)
• DemurrageCheck, how it works: When the product prepares a letter, and the reminders

This guide is general information about a federal rule, not legal advice. DemurrageCheck is software, not a law firm. Read the rule itself for its exact wording.

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