Table of Contents
- How FBA fees are calculated, and where they go wrong
- The overcharges worth auditing
- Where to check your dimensions and fees
- How to request a remeasure and a refund
- Mistakes sellers make with fee overcharges
- When to automate fee auditing with a service
How FBA fees are calculated, and where they go wrong
Every FBA fulfillment fee is driven by two measured inputs: the unit's weight and its dimensions. Together they place the product in a size tier, and the tier sets the per-unit fee you pay on every sale. The system works as long as the measurements are right. The problem is that Amazon measures products in the warehouse with automated equipment, and those readings are not always accurate.
When a unit is recorded heavier or larger than it truly is, it gets bumped into a higher size tier. From that point you are not overcharged once — you are overcharged on every single order until someone notices and corrects the record. That recurring quality is what makes fee errors so different from lost inventory. A lost unit is one event. A measurement error is a tax on every future sale of that ASIN.
You can sanity-check the economics of a corrected fee against your own numbers using our free FBA calculator, which breaks down referral and fulfillment fees against your cost and price.
The overcharges worth auditing
Fee overcharges cluster into a few recognizable patterns. Each is recoverable when you can show the charge was based on an incorrect input.
- Dimension errors. The recorded length, width or height is larger than the product's true packaged size, pushing it into a bigger tier.
- Weight errors. The recorded unit weight exceeds the real weight, raising the fulfillment fee directly.
- Wrong size-tier assignment. Even with roughly correct measurements, the unit may be placed in the wrong tier and charged accordingly.
- Fees not reversed on returns or cancellations. A fulfillment or referral fee that should have been credited back on a refunded or cancelled order but was not.
The last category overlaps with returns work, which we cover in the guide to FBA customer return reimbursements — fee reversal and unit reimbursement often travel together on the same refunded order.
Where to check your dimensions and fees
| Report | What it tells you |
|---|---|
| FBA fee preview / estimated fees | The size tier, recorded dimensions and weight Amazon is using per ASIN |
| Product dimension / measurement record | The exact figures driving the fee, to compare against the true product |
| Transaction / fee reports | What you were actually charged per unit and per order over time |
| Reimbursements report | Whether any fee correction or credit has already been issued |
The signal is a recorded measurement that is clearly larger than your product's real packaged dimensions or weight, matched to a fee charged at the inflated tier. That gives you a precise, evidence-based correction request rather than a general complaint.
How to request a remeasure and a refund
- Establish the true measurement. Record the product's real packaged weight and dimensions, ideally with supplier specifications to support them.
- Compare against Amazon's record. Identify the exact gap between the recorded and actual figures and the tier it changed.
- Request a remeasure. Ask Amazon to re-measure the unit so future fees are charged at the correct tier.
- Claim the historical overcharge. Once the measurement is corrected, pursue a refund of the fees charged at the wrong tier within the eligible window.
Fixing the measurement stops the bleeding going forward; claiming the historical difference recovers what was already overpaid. Both steps matter, and sellers frequently do the first while forgetting the second.
Mistakes sellers make with fee overcharges
- Trusting the recorded dimensions. Sellers assume the fee preview is correct because it is precise, but precision is not the same as accuracy.
- Fixing the measurement but not claiming the past. Correcting the tier going forward leaves the historical overcharge unrecovered.
- Dismissing small per-unit gaps. A few cents per order on a fast seller compounds into a large cumulative overcharge.
- Treating fees as separate from reconciliation. Fee errors sit alongside lost inventory, damage and returns, so they belong in the same disciplined audit rather than a one-off check.
When to automate fee auditing with a service
Checking dimensions on a handful of ASINs is straightforward. Doing it across a growing catalog, re-checking after Amazon re-measures, and tracking recurring overcharges per unit over time is the kind of repetitive analysis that quietly costs more in lost margin than it would to delegate.
Fee recovery is one element of a complete Amazon FBA reconciliation workflow that also covers lost units, returns and damage. For the full picture, start with the Amazon FBA reimbursement guide or the 2026 reimbursement policy summary. For an account-specific answer, request a free audit through our contact page.
Paying the Wrong Fee on Every Sale?
We compare Amazon's recorded measurements against your real product, flag the overcharged ASINs, and pursue both the correction and the historical refund.
