Size tier misclassification is the most expensive FBA error because it compounds silently — applied to every shipment until you find it and dispute it. Here's exactly how to detect it and recover what you're owed.
Think Amazon put your product in the wrong size tier? Pick the tier you were charged as and see the correct fulfillment fee — if your real dimensions fit a smaller tier, you're overpaying. Free, 100% offline.
100% offline. Your inputs never leave your device. Fulfillment fees only — storage, referral and other fees are not checked here. Reconcile with your current Seller Central fee before disputing.
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These are the current 2026 US fulfillment fees for items priced $10–$50. A product sitting at a tier boundary is the highest-risk zone for overcharges.
| Size Tier | Max Weight | Fee (price $10–$50) | Risk Zone |
|---|---|---|---|
| Small Standard | ≤ 2 oz | $3.32 | — |
| Small Standard | ≤ 6 oz | $3.45 | — |
| Small Standard | ≤ 16 oz | $3.96 | Boundary |
| Large Standard | ≤ 4 oz | $3.73 | Boundary |
| Large Standard | ≤ 1.25 lb | $5.04 | — |
| Large Standard | ≤ 3 lb | $6.67 | — |
| Small Bulky | ≤ 1 lb base | $7.55 | — |
Nothing changed on your end — same product, same packaging — but your fee per unit went up. This is the clearest signal of a Cubiscan remeasurement error.
You know your product weighs 5oz, but you're being charged a fee that only makes sense for products over 1lb. The size tier in Seller Central doesn't match your product.
Your profit per unit keeps dropping but your product price and COGS stayed the same. Hidden fulfillment fee increases are often the invisible cause.
Open your FBA Fee Preview Report and compare the dimensions Amazon has on file against your manufacturer's specs. Even a 0.2 inch difference can trigger a higher tier.
Download it from Reports → Fulfillment in Seller Central. Find the ASIN with the wrong tier. Note the dimensions and weight Amazon has on file.
Contact Seller Support and request a Cubiscan remeasurement for the ASIN. Provide your manufacturer's specifications as evidence for the correct dimensions.
Once the tier is corrected, file a separate claim for all historical overcharges. Include every affected order number and the exact overcharge per unit.
90-day claim window. Amazon only allows reimbursement claims for fulfillment fee overcharges within 90 days of the charge. If you don't file in time, that money is permanently gone. Don't wait to audit.
Amazon typically processes remeasurement requests within 3–5 business days. If the error is confirmed, the size tier correction applies to all future orders immediately. Historical overcharges require a separate reimbursement case filed within the 90-day window.
Fulfillment fee overcharge claims must be filed within 90 days of the charge date. There is no way to extend this window — Amazon closes these claims automatically once the deadline passes. If you've been overcharged for months, act immediately to recover what is still within the open window.
If Amazon's remeasurement confirms their current dimensions, escalate by submitting third-party measurement evidence — a certified scale reading or official packaging specifications from your manufacturer. Escalated cases with precise documentation have a significantly higher approval rate than initial submissions.
Before sending a new product to FBA, request a manual dimension review via Seller Central. Cross-check your packaging dimensions against Amazon's current size tier table before each shipment. Products near tier boundaries — especially between Small Standard and Large Standard — carry the highest misclassification risk and should be audited first.
Sellers with 200+ units per month who catch a Small-to-Large Standard boundary error typically recover $400–$1,500 in historical overcharges before the 90-day cutoff. High-volume sellers with multiple affected ASINs have recovered $10,000 or more in a single audit. The earlier you audit, the more open claim windows remain.
You need the FBA Fee Preview Report from Seller Central under Reports → Fulfillment. It lists every ASIN's current size tier classification, recorded dimensions, and estimated fee per unit. FBA Fee Auditor reads this CSV directly and flags every overcharge automatically — no manual spreadsheet work required.
FBA Fee Auditor audits your entire catalog offline — no subscription, no cloud, instant results.
Four free tools, one job: catch and recover the FBA fees Amazon got wrong. Start anywhere — they all point back to the full auditor.
Disclaimer: FBA Fee Auditor is an independent tool created by Smart Local Tools. It is not affiliated with, endorsed by, or in any way officially connected to Amazon.com, Inc. or any of its subsidiaries. Amazon, Fulfillment by Amazon (FBA), and Seller Central are trademarks of Amazon.com, Inc.
The fee tables included in this tool are based on publicly available information from Amazon Seller Central and reflect rates as of January 15, 2026 (US) and February 1, 2026 (DE). Fee structures may change at any time. Smart Local Tools makes no guarantee that the fee tables are complete, current, or error-free. Always verify results against the official Amazon Seller Central fee schedule before filing a reimbursement case.
This tool is provided "as is" without warranty of any kind. Smart Local Tools is not liable for any financial decisions made based on the output of this tool. Use of this tool constitutes acceptance of these terms.