Proof in every line1. Confirm it is really an overcharge
Before writing anything, check the agreement that applied on the invoice date, including addendums and any rate change you approved by email. Some differences have a legitimate reason, such as a requested repack, special project work or a published annual increase you accepted.
2. Put the numbers side by side
For each disputed fee, write down four things: the invoice number and line (or order number), the quantity billed, the rate you were charged and the rate in your agreement. The difference is quantity × (charged rate − agreed rate). Keep it to arithmetic anyone can check in ten seconds.
3. Attach the evidence once, clearly
Include the clause or rate-card row that sets the rate, the invoice lines in question and, if relevant, your order or inventory records. One tidy PDF beats ten screenshots. BillProofs builds this evidence pack automatically for every finding.
4. Ask for a specific outcome
Request a credit of a stated amount on the next invoice, and ask them to correct the rate going forward. A dispute that ends with "please look into this" tends to stall; one that ends with a number gets processed.
An email you can adapt
Subject: Credit request: invoice [number], [fee name] billed above agreed rate
Hi [name],
On invoice [number] dated [date], [fee name] was billed at [charged rate] for [quantity] units. Our agreement ([document], [section or rate-card row]) sets this at [agreed rate]. That is a difference of [amount].
I've attached the agreement extract and the invoice lines. Could you please confirm a credit of [amount] on our next invoice and update the rate in billing so it applies going forward?
Thanks, [your name]
5. Track it until the credit posts
Note the date you sent the request, who replied and the credit they agreed. Then check the following invoices until it actually appears. Promised credits that never arrive are one of the most common billing gaps.
6. Fix the cause, not just the invoice
If the same rate is wrong every month, ask for it to be corrected at the source. Then keep checking: a rate fixed once can drift again when systems or contracts change.
Questions
How long do I have to dispute a 3PL invoice?
It depends on your agreement. Many 3PL contracts set a dispute window, often a set number of days after the invoice date, so check yours and raise issues promptly.
Should I withhold payment while disputing?
Check your agreement first. Many contracts require paying undisputed amounts on time, and withholding the full invoice can create late fees or service holds. Paying the undisputed part and disputing the specific lines is usually safer.
What if the 3PL says the rate changed?
Ask which document or notice changed it and from what date. If you agreed to it, the new rate applies from that date; if you did not, ask for the original rate to be honoured.
Does BillProofs contact my 3PL for me?
No. BillProofs finds the differences and prepares the evidence and a draft message. You decide what to send, so your relationship with your 3PL stays in your hands.
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