How to audit a 3PL invoice, line by line
Updated · Rotomal
To audit a 3PL invoice, put three things side by side: the contract or rate card, the invoice lines, and your own order and inventory data for the same period. Recompute each charge from your data at the contracted rate and unit, starting with the biggest lines (usually storage and pick and pack), then check that every receiving, return, accessorial and minimum charge has a matching event or contract clause. Anything that differs or has no basis goes on a dispute list, sent within the dispute window in your contract.
What you need
- The signed contract or rate card, plus every amendment and any email where a rate was agreed.
- The invoice detail, not only the summary: most 3PLs can export line items as CSV.
- An order export from your store or WMS for the same dates, with units per order.
- Inbound receipts (dates, pallets or cartons) and on-hand inventory snapshots.
The checks, in order of usual size
| Charge | Check it against | Common errors |
|---|---|---|
| Storage | On-hand units or pallets per day or month, at the contract unit | Billing on stock that has shipped, wrong unit (pallet vs bin), long-term tier applied early |
| Pick and pack | Orders and units per order from your export | Extra picks on single-item orders, wrong tier, packaging charged when you supply boxes |
| Receiving | Inbound shipments by pallet, carton or container | Charged per carton when the contract says per pallet, duplicate receipts |
| Returns | Returns actually processed | Fees on returns that were never received |
| Accessorial and projects | A contract clause and a request from you | Hourly work with no request, relabelling caused by the warehouse |
| Minimum fee | Total activity for the month | Minimum added on top instead of as a floor |
Eightx's July 2026 compilation of US rate guides puts storage at $8 to $40 per pallet per month and monthly minimums from $337 to over $2,000, so a single unit or tier mistake on storage can outweigh many small lines.
How to raise what you find
- Group findings by cause, not by line, and show the evidence for each: the contract clause, the invoice line and your data.
- Separate clear errors from questions. A charge the contract does not price is a question to ask, not a mistake to claim.
- Send it within the dispute window in your contract, and ask for a credit note against the next invoice.
- Fix the cause at the warehouse, such as an outdated pallet count, so it does not recur.
If you want it done for you
Ratecard Audit does this recalculation for you: the scope confirmed by email before you pay, then a fixed-price audit of 3 or 12 months from $290, with a findings spreadsheet and a dispute letter ready to send.
Questions
Is there a free tool for this?
Warp offers a free warehouse invoice audit tool that recomputes pallet storage days, checks storage against the contract rate you enter, and flags handling lines with no matching event, pick and pack above the order count, duplicates and minimum fees. You run it yourself from the invoice file and the rates you type in.
How often should I audit?
At least before every renewal, and monthly if invoices vary a lot. A monthly check is easier than a yearly one because the data is fresh and still inside the dispute window.
Sources
- Eightx: 3PL all-in cost per order (July 2026) Source: eightx.co
- Warp: free warehouse invoice audit tool Source: wearewarp.com
- ShipBob: fulfillment pricing structure Source: shipbob.com