FBA Reimbursement Claims – What Amazon Owes You

Amazon probably owes you money right now. Not because of bad faith but because at FBA’s scale inventory errors are inevitable. Lost units. Damaged returns. Customer refunds where the item was never sent back. Fee overcharges from incorrect dimension records. Most sellers leave $1,500 to $3,000 per year unclaimed because they do not know what to look for, which reports to pull, or that the claim window is now approximately 60 days not the 18 months it used to be.

That 60-day window is the most important number in this guide. Miss it and the reimbursement is gone permanently.

What Changed – The Two Policy Shifts That Make Active Management Critical

Two changes to Amazon’s reimbursement policy made passive management obsolete. Both are now fully in effect in 2026.

Change 1: Manufacturing cost replaces retail price (effective March 10, 2025)

Before March 2025 Amazon reimbursed lost and damaged FBA inventory at approximately the retail selling price. A product selling for $40 might receive a reimbursement close to $40.

Effective March 10, 2025 Amazon reimburses at manufacturing cost. The same $40 product that cost $12 to source now receives approximately $12 in reimbursement. Sellers report recovery amounts dropping 50 to 75 percent on average since the change took effect.

Manufacturing cost as defined by Amazon means your cost to source the product from a manufacturer, wholesaler, or reseller. It excludes shipping, handling, customs duties, and other costs.

The critical implication: If your cost of goods fields in Seller Central are missing, zeroed out, or inaccurate, Amazon uses its own internal estimate to calculate your reimbursement. Internal estimates are consistently lower than accurate seller-provided cost data. Entering accurate manufacturing cost data in the Inventory Defect and Reimbursement portal is now a direct revenue protection action not an optional administrative task.

Change 2: Claim window shortened to approximately 60 days

The old reimbursement claim window was 18 months. In late 2024 Amazon shortened most claim windows to approximately 60 days from the date the discrepancy surfaces.

At 18 months, quarterly or annual audits were sufficient to catch eligible claims. At 60 days, monthly auditing is the minimum viable rhythm. Sellers who check reimbursements quarterly are forfeiting months of eligible claims by design.

For the complete breakdown of all 2026 FBA fee and policy changes, see Amazon FBA Fees Explained.

Five Claim Categories – What Amazon Owes You

Category 1: Lost inventory in the fulfillment network.
Units that enter Amazon’s warehouse but never make it to a customer. This includes units lost in transit between fulfillment centers, units missing from receiving scans, and units that disappear after a customer return is processed back into inventory.

Amazon automatically reimburses some lost inventory cases but does not catch everything. The automatic system is not exhaustive. Independent reconciliation through your own report audit is required to confirm what has been paid versus what is outstanding.

Category 2: Damaged inventory.
Units damaged in Amazon’s warehouse before they ship, or damaged in transit under Amazon’s handling. Amazon is responsible for the condition of items from the moment they enter the fulfillment network. Units marked as damaged warehouse in your inventory adjustment report without a corresponding reimbursement credit are eligible claims.

Look for negative adjustment codes in your Inventory Adjustments report: E1 (damaged), E3 (damaged at fulfillment center), E7 (removed by customer), and M (missing or lost). These codes identify events that should have generated a reimbursement credit. Any of these codes without a corresponding credit line is a potential unclaimed reimbursement.

Category 3: FBA fee overcharges.
Fulfillment fees are calculated based on the dimensions and weight Amazon has on file for your product. If Amazon’s system has incorrect dimensions, if Amazon re-measured your product and recorded a larger size than actual, or if a fee calculation error occurred, you are paying more than the correct amount on every unit sold.

Fee overcharge claims require documented actual packaged dimensions before filing. If your declared dimensions in Seller Central do not match your product’s actual packaged dimensions, Amazon may deny the overcharge claim even if their on-file dimensions are wrong. Measure your product in its shipped packaging with calipers or a tape measure and document this before opening a case.

Category 4: Customer returns not returned.
When a customer receives a refund but never actually returns the product to Amazon’s warehouse, Amazon is supposed to reimburse the seller after 45 days. This is a common failure point in Amazon’s automation.

Check your Returns Report against your Reimbursements Report. If a refund was issued more than 45 days ago and the item is not back in your inventory (and no reimbursement exists), you are owed a claim.

Category 5: Destroyed or disposed of without consent.
Units that Amazon destroys without seller authorization (often due to being marked “unsellable”) are eligible for reimbursement if the seller did not set up automated disposal or if the item was destroyed prematurely.

How to Audit and Claim

Auditing is a process of comparing reports.

1. Download the Inventory Ledger Report. This is your source of truth for all inventory movements.
2. Download the Reimbursements Report. This shows what Amazon has already paid you for.
3. Download the FBA Customer Returns Report. This tracks what customers said they were returning.

Cross-reference these. Look for “Lost” or “Damaged” status in the Ledger that does not have a matching ID in the Reimbursements report. Look for “Refunded” items in the Returns report that never shows a “Unit Returned to Warehouse” event in the Ledger.

Filing the Claim – Best Practices

When you find a discrepancy, open a case in Seller Central under “FBA Issue” -> “Other FBA Issue.”

• Provide the Transaction ID. Never just say “I’m missing a unit.” Give the specific shipment ID or transaction ID from the report.
• Keep it simple. Use a bulleted list. One discrepancy per case unless they are identical issues for the same SKU.
• Attach proof. For fee overcharges, attach photos of the item on a scale or next to a ruler. For cost of goods claims, keep your manufacturer invoices ready if Amazon challenges your provided manufacturing cost.

If you are a high-volume seller, manual auditing becomes a full-time job. This is where automated reimbursement tools (like Helium 10’s Refund Genie or specialized services like Carbon6) become ROI-positive. They take a percentage of the recovery but usually find significantly more than a seller doing manual spot-checks.

Protect your margins. Check your reports monthly. Amazon’s error rate is a hidden tax that you have the right to reclaim.