Zenmul
Per diem and detention
Per diem bill checks for drayage trucking companies
For small drayage companies at the Ports of Los Angeles and Long Beach, running 3 to 50 trucks. I check every per diem and detention line against your gate records and the FMC billing rules, then prepare the dispute file. You send it.
Per diem bills keep counting on days your trucks could not move the box.
Most of these are not obvious from the total. They show up when each day on the bill is checked against the gate and appointment records.
- Days the terminal gate was closed, still billed as per diem.
- Days there was no return appointment for the empty, still billed.
- An invoice issued more than 30 days after the charge was last incurred. That charge does not have to be paid (46 CFR 541.7).
- An invoice missing a required detail. The obligation to pay that charge is eliminated (46 CFR 541.5 and 541.6).
- You have 30 days to dispute an invoice, and the billing party must try to resolve it within 30 days (46 CFR 541.8).
This is a plain summary of the published rules, not legal advice. Read the guide: the FMC billing rules
A trucking company disputed $510 of closed port days, and the FMC agreed.
TCW, a trucking company, got a $1,490 detention bill from Evergreen. $510 of it covered May 23 to 25, 2020, when the Port of Savannah was closed for Memorial Day.
- TCW paid the bill, filed an FMC small claim and won.
- December 2022: the full FMC agreed.
- July 2024: the D.C. Circuit sent the case back to the FMC.
- The FMC held its position.
- April 2026: the D.C. Circuit unanimously upheld the FMC.
Every bill has its own facts. This case shows what was decided for TCW, not what will happen with your bill.
Per diem you already paid is not necessarily closed.
Under an FMC rule published September 1, 2026, charge complaints about charges assessed on or after June 16, 2022 have no statute of limitations. This covers importers, exporters, forwarders and truckers.
A look back goes through the per diem and detention you have already paid since June 16, 2022, and sorts each charge by whether it is worth raising.
You decide what to file. I prepare the file.
Small extra days add up fast.
This is an example, not a client result. Per diem often runs around $175 a day on a dry container and about $375 a day on a reefer.
Example: one box a week gets billed 2 extra days.
2 days x $175 a day = $350 a week.
That is about $1,500 a month, from just one box a week.
Every day on every per diem bill.
Each line is checked against your own records, not the carrier's total.
- Each billed day against the gate out and empty return dates.
- Days the terminal gate was closed.
- Days with no return appointment, against your appointment screenshots.
- Free time counted correctly before billing starts.
- The invoice date, against the 30 day limit.
- The required invoice details.
- The same container billed twice.
- The 30 day dispute deadline for every invoice, so none slip by.
Get the per diem bill checklist
A two page checklist to run every per diem or detention invoice through before you pay it: the 30 day invoice limit, the required invoice details, closed gate and no appointment days, the math, the dispute deadline and the proof to keep.
PDF, 2 pages. No email needed. Not legal advice.
Get the per diem bill checklistSend. Check. File. You send it.
The same four steps for every bill.
STEP 01 / SEND
Email the bills
Send the per diem and detention invoices, with the gate records and appointment screenshots for those containers.
STEP 02 / CHECK
I check every line
Every billed day is checked against your dates, closed gate days, missing appointments and the FMC billing rules.
STEP 03 / FILE
Get the dispute file
Every charge is marked dispute, fair or missing proof, with a dispute letter for each invoice worth raising.
STEP 04 / DISPUTE
You send it
You send the dispute to the carrier yourself, before the deadline. I never contact the carrier.
Send what you have.
Black out anything private before you send it, such as driver details, bank details or rates you do not want shared.
- The per diem and detention invoices, as PDFs or exports.
- Gate records, with gate out and empty return dates for each container.
- Screenshots showing no return appointments were available, if you have them.
- Any emails or notices about closed gates, if you have them.
You stay in control of every dispute.
I check the bills and prepare the dispute file. Everything else stays with you.
- I never ask for your logins or portal passwords.
- I never contact the carrier. You send every dispute.
- I am not a lawyer or a customs broker, and nothing here is legal advice.
- I do not promise results. If a charge is fair, I tell you it is fair.
Common questions
Who is this for?
Small drayage trucking companies at the Ports of Los Angeles and Long Beach, running 3 to 50 trucks, that pay per diem and detention bills.
Can a trucking company be billed per diem?
Yes. The rule section that limited who could be billed (46 CFR 541.4) was struck down in September 2025 and removed on December 29, 2025. That makes checking each bill line by line more important, not less.
I already paid. Is it too late?
For charges assessed on or after June 16, 2022, a charge complaint has no statute of limitations. Whether a charge is worth raising depends on the amount and the evidence, and that is what the check tells you.
Will you contact the carrier for me?
No. I prepare the dispute file and you send it. I never negotiate on your behalf and never need your portal login.
What if I do not have all the records?
Send what you have. Many checks only need the invoice and the container dates. Anything that cannot be checked without more records gets marked missing proof, not guessed.
Is this legal advice?
No. I am not a lawyer. This is a plain summary of the published rules, not legal advice.
Let's discuss your per diem bills.
Write a few lines about the bill that is bothering you. I will check every line and tell you what I find, including when a charge is fair.
Email nazmul@zenmul.com