Once you have paid a freight bill, disputing it stops being a short-pay conversation and becomes a claim. The freight overcharge claim process for motor carriers lives in 49 CFR Part 378, and the part almost nobody knows is the clock: under 49 CFR 378.8, the processing carrier must pay, decline to pay, or settle each written overcharge claim within 60 days of receiving it, unless you agree in writing to an extension for extenuating circumstances.
That single sentence changes the tone of your follow-up. You are not asking a carrier when it might get around to your refund. You are asking it to meet a stated deadline that started the day your written claim arrived.
Three things have to be true for the clock to help you. The claim has to be written. It has to carry the documentation the rule names. And you have to be inside the outer statutory windows, which are considerably shorter than most AP teams assume. All three are below, along with what to do when the money went to a broker rather than a carrier, where Part 378 does not reach.
Why a paid invoice is a different problem
Before payment, your leverage is the money. You short-pay the disputed line, release the rest, and the carrier comes to you. That path depends on catching the error while the invoice is still open, which is why matching the rate confirmation against the carrier invoice before approval is worth more than any recovery effort afterward.
After payment, the leverage inverts. The carrier holds your money, the load is closed, and you are the one initiating. That is usually nobody’s fault: overcharges surface late because the error was invisible at approval time. A fuel surcharge computed on the wrong index week looks exactly like a correct one until someone recomputes it.
What Part 378 does is give the post-payment path a defined shape: definitions, a documentation standard, an investigation duty, and a resolution deadline. Use the shape. A claim that reads like a regulated filing gets routed to the carrier’s claims desk. An email that reads like a complaint gets routed to whoever answers first.
What counts as an overcharge
49 CFR 378.2 defines the three things this process covers, and the distinctions matter because they change what you attach.
Overcharge. The definition points to 49 U.S.C. 14704(b): charges collected in excess of those applicable. In practice this is the rated-wrong case. The rate applied was not the agreed rate, the class was wrong, the weight was wrong, the surcharge percentage did not match the index, the accessorial was not authorized. To prove it you need the correct basis, meaning the contract, tariff item, or index the right number comes from.
Duplicate payment. Two or more payments for transporting the same shipment. This is the cleanest claim in freight because you do not need to argue about what was owed. You only need to show the same move was paid twice. The trap is telling a true duplicate from a legitimate rebill or a corrected invoice, which is a matching problem before it is a claims problem, worked through in how to detect duplicate freight invoices.
Overcollection. Money collected that was not owed at all, as opposed to too much of something that was.
Sort your finding into one of those three before you write. An overcharge claim argues about the correct amount. A duplicate payment claim argues about identity of shipment.
What the claim has to contain
49 CFR 378.4 sets the documentation standard. The claim must be accompanied by the freight bill, plus the rate, classification, weight or tariff authority relied on, plus payment information.
Read the components carefully, because each one answers a different question:
| Element the rule names | The question it answers | What you actually attach |
|---|---|---|
| The freight bill | Which shipment and which charges | The carrier’s invoice, with the disputed line marked |
| Rate, classification, weight or tariff authority relied on | What the correct charge should have been | Rate confirmation, contract rate page, tariff item number and version, NMFC item, certified scale ticket, or index publication |
| Payment information | That you actually paid, and how much | Check number and clear date, ACH trace or remittance advice, credit card settlement |
A second half of 378.4 is worth knowing: inadequate documentation alone cannot disqualify a claim. That does not license a sloppy filing, and it does not mean a carrier must pay a claim you have not supported. It means a carrier cannot dispose of your claim purely on a paperwork technicality without engaging the substance. If you get back “claim closed, insufficient documentation” with no analysis, ask which document is missing and refile with it.
The most common gap is the second row. People attach the invoice and the proof of payment and skip the authority for the correct number, so the claim asserts an overcharge without establishing the right charge. Whatever the underlying issue is, the correct-basis document is the one that does the work: for a fuel surcharge dispute it is the contract formula plus the published index week, the mechanics of which are in how to calculate a truckload fuel surcharge from the DOE index. For a detention claim it is the free time terms and the timestamps, covered in the documents that prove a detention charge.
The 60-day clock, and what actually starts it
Two sections work together here, and the sequence is the useful part.
49 CFR 378.5 says that on receipt of any claim, written or otherwise, the processing carrier must promptly begin an investigation and open a file. So a phone call does obligate the carrier to start looking. But the same rule is explicit that only a written claim starts the 378.8 clock.
49 CFR 378.8 is the deadline: pay, decline to pay, or settle within 60 days of receipt, absent a written agreement to extend for extenuating circumstances.
Three practical consequences.
Put it in writing, always. A call to your rep may get the credit faster, and often does. It does not start the clock. Send the written claim regardless, even if you expect the phone call to resolve it. It costs you one email and it converts a favor into an obligation.
Date the receipt, not the sending. The 60 days run from receipt. Send in a way that produces a receipt record: an email to the carrier’s published claims address, a portal submission with a confirmation number, or certified mail for large amounts. Record the date in your own file the day you send.
“Decline to pay” satisfies the rule. This is the honest limit. The carrier meeting its 60-day duty is not the same as the carrier paying you. A written declination inside 60 days is compliant, and it is also the event that starts other clocks running against you. Which brings up the part that costs real money.
The outer deadlines that end the argument
The 60-day rule governs the carrier’s response. Separate statutes govern how long you have to bring the claim at all, and those are the ones that quietly close.
Under 49 U.S.C. 14705, a shipper must begin a civil action to recover overcharges within 18 months, or file a complaint with the Board or Secretary within 3 years. Claims accrue on delivery or tender of delivery, not on the date you discovered the error and not on the date you paid. There is a 6-month extension when the carrier issues a written disallowance, plus 90 days where the carrier has begun collection action, and a 3-year period for Federal-government shipments. The same section gives the carrier 18 months from accrual to sue you for unpaid freight charges, which is worth knowing when a carrier surfaces an old balance.
Separately, 49 U.S.C. 13710 gives you 180 days from receipt of the original bill (or a subsequent bill) to contest it and preserve your right to challenge. The mirror provision requires a carrier to bill additional charges within 180 days of your receipt of the original bill to preserve its collection rights.
Note what that means together. Eighteen months is the litigation deadline. One hundred eighty days is the contest deadline that keeps your challenge alive in the first place. Treat 180 days from bill receipt as your real working limit, not 18 months.
| Clock | Length | Runs from | Source |
|---|---|---|---|
| Carrier must resolve a written overcharge claim | 60 days | Receipt of the written claim | 49 CFR 378.8 |
| Carrier must refund an overpayment it discovers itself | 30 days | Carrier’s discovery | 49 CFR 378.9 |
| Shipper must contest a bill to preserve the right to challenge | 180 days | Your receipt of the bill | 49 U.S.C. 13710 |
| Carrier must bill additional charges to preserve collection rights | 180 days | Your receipt of the original bill | 49 U.S.C. 13710 |
| Shipper must sue to recover overcharges | 18 months | Delivery or tender of delivery | 49 U.S.C. 14705 |
| Shipper may file a complaint with the Board or Secretary | 3 years | Delivery or tender of delivery | 49 U.S.C. 14705 |
These interlock with the credit and billing rules in Part 377, and with the loss and damage clocks in Part 370, which are different numbers entirely. The full set is laid out in the freight billing deadlines reference. Do not carry the overcharge numbers over to a damage claim: those run on 9 months to file and 2 years to sue under 49 U.S.C. 14706(e)(1), with a 120-day carrier response window.
The duty that runs the other way
49 CFR 378.9 is the section worth quoting to a carrier that has gone quiet, because it puts duties on the carrier without you filing anything.
When the carrier itself discovers an overpayment, duplicate payment, or overcollection, it must refund within 30 days. Not on request. On discovery.
The section also handles unidentified payments, money the carrier received but cannot match to a payor. The carrier must notify the payor within 60 days where it can, may treat the funds as its own after 90 days without a response, and once it receives payor information must refund or respond within 14 days.
Two things follow. First, if you have ever paid an invoice with a bad or missing reference number, that money may be sitting in a carrier’s unidentified-payments account with a 90-day fuse on it. Reconcile remittances against applied payments, not just against invoices issued. Second, a carrier that finds a systemic billing error across many of your loads owes refunds on all of them within 30 days of finding it, whether or not you filed a claim on each one. Worth raising when a single claim reveals a pattern.
Where Part 378 does not reach
This is where posts on this subject usually overstate, so be precise about the boundary.
Brokers. Part 378 governs carriers. If you paid a broker, your recovery runs on your contract with that broker, not on 49 CFR 378. The broker may in turn have a Part 378 claim against the underlying carrier, but that is their claim, not yours. Read your broker agreement for its own billing correction and dispute terms, because those terms, not the CFR, are what you are enforcing.
Contract carriage. Much truckload moves under contract rather than common carriage, and a transportation services agreement can specify its own dispute procedure, notice period, and remedies. Where your contract sets a shorter notice window than the statutes, the contract is what your counterparty will hold you to. Check the agreement before you rely on a statutory window.
Parcel. Parcel carriers operate under their own published service guides and terms, with their own refund request windows that are typically much shorter than anything here, often measured in days for service failures. Do not apply the 180-day contest window to a parcel account without reading the service guide.
Other modes. The related credit rules in Part 377 are written for for-hire non-exempt motor carriers and household goods freight forwarders. Ocean demurrage and detention billing runs on a separate FMC regime in 46 CFR Part 541, with its own 30-day invoice issuance and mitigation-request windows.
The honest framing for a mixed operation: the 60-day rule is a real lever on domestic motor carrier freight paid to the carrier. Everywhere else your rights come from the contract you signed, and you should say so plainly to your own team rather than citing a CFR section that does not apply.
What to send
Keep it structured. The person reading it processes claims all day and wants to find the elements fast.
Subject: Overcharge claim - PRO 1234567 - invoice 48213 - $118.00
Claim type: Overcharge (49 CFR 378.2)
Claimant: [Company], [address], [AP contact and email]
Carrier: [Carrier name], SCAC [XXXX]
Shipment: BOL 88214, PRO 1234567, picked up 08/12/2026,
Dallas TX to Memphis TN, delivered 08/13/2026
Invoice: 48213, dated 08/15/2026, total $2,458.00
Paid: check 10442, cleared 09/09/2026, $2,458.00 in full
Amount claimed: $118.00
Basis of claim:
Fuel surcharge was billed at 31.5%. Our contract rate agreement
(attached, section 4) computes the surcharge from the EIA weekly
national on-highway diesel average for the week preceding pickup.
The applicable published average produces 28.9%. The difference on
this load is $118.00.
Attached:
1. Carrier invoice 48213
2. Rate confirmation and contract rate agreement, section 4
3. Published index value for the applicable week
4. Remittance advice and cleared check 10442
Please confirm receipt and your claim file number. We are filing
this as a written overcharge claim under 49 CFR 378.4 and note the
resolution period in 49 CFR 378.8.
[Name] | [Title] | [Phone] | [Email]Why it is shaped that way: the identifiers come first so the file can be pulled before anyone reads your argument, the basis is one paragraph naming the correct authority and the arithmetic rather than a narrative, and the attachments are numbered so a declination has to say which one it disputes. Ask for a claim file number specifically. It gives you a reference for follow-up and confirms the carrier opened the file that 378.5 requires.
Running this as a process, not a one-off
A single claim is worth filing. What recovers money is filing every one, on a cadence, with the same structure.
- Reconcile after payment, not only before. Post-payment audit catches what approval missed. If your team only reviews open invoices, every error that survives approval is permanently lost.
- Age your claims. Log the filing date and the 60-day date. Follow up at day 30 and again at day 55 referencing 378.8. Most carriers respond faster once they see you tracking it.
- Batch by pattern, not by load. Ten loads with the same wrong surcharge percentage is one claim with a schedule attached, and it triggers the 378.9 discovery duty on the rest.
- Track outcomes, not filings. Recovered dollars are the number. A claim filed and never chased is worse than not filing, because it tells you the process works when it does not.
- Watch the 180-day line. Anything approaching 180 days from bill receipt goes to the front of the queue.
- Know when to stop. Small claims on a good carrier relationship have a cost that is not on the invoice. Decide a threshold and stick to it.
The last point deserves the honest version. Post-payment recovery is slower, lower-yield, and more relationship-expensive than catching the error before you pay. It is worth doing, and it should be your second line of defense rather than your first. Whether you run that pre-payment review in-house or buy it, the economics of the options are compared in freight audit cost and pricing models.
The checklist
- Classify the finding: overcharge, duplicate payment, or overcollection, per 49 CFR 378.2.
- Confirm you paid, and pull the payment record.
- Pull the authority for the correct charge: contract, tariff item, index, scale ticket, or class basis.
- Check who you paid. Carrier means Part 378. Broker means your contract.
- Check the calendar: days since you received the bill, against 180; months since delivery, against 18.
- File in writing, with the 378.4 elements attached and numbered.
- Record the filing date and calendar the 60-day date from receipt.
- Follow up at day 30 and day 55, citing 49 CFR 378.8.
- On a declination, read what they actually disputed and decide: refile with better documentation, or escalate.
- When one claim reveals a pattern, raise 378.9 and ask for the rest.
Sources
- 49 CFR 378.2, Definitions of overcharge, duplicate payment and overcollection (Cornell LII)
- 49 CFR 378.4, Documentation required with an overcharge claim (Cornell LII)
- 49 CFR 378.5, Investigation and claim file on receipt (Cornell LII)
- 49 CFR 378.8, Sixty-day resolution period for written overcharge claims (Cornell LII)
- 49 CFR 378.9, Unidentified payments and carrier-discovered overpayments (Cornell LII)
- 49 U.S.C. 14705, Limitation periods for overcharge and freight charge actions (Cornell LII)
- 49 U.S.C. 13710, Billing and contesting windows (Cornell LII)
- 49 U.S.C. 14706, Carmack Amendment claim and suit periods (Cornell LII)
- 49 CFR Part 377, Extension of credit to shippers (Cornell LII)
- 46 CFR Part 541, FMC demurrage and detention billing requirements (Cornell LII)