How to Claim Amazon FBA Reimbursements in 2026 (Complete Guide)

Amazon's FBA system handles millions of units daily across hundreds of fulfillment centers. Units get lost in the warehouse, damaged during handling, miscounted during receiving, and misclassified for fee purposes. Amazon automatically reimburses some of these errors, but not all — and not always at the correct amount. The rest require you to find the discrepancy, document it, and file a claim through Seller Support.

Most sellers never do this systematically. The ones who do recover 1-3% of their annual revenue. On a $500K business, that's $5,000 to $15,000 per year — money that's already yours, sitting in Amazon's system waiting for you to claim it.

What changed in 2026

Several significant changes affect how FBA reimbursements work in 2026:

• Manufacturing cost reimbursements: For many claim types, Amazon now reimburses at estimated manufacturing cost rather than retail price. This reduces the value of individual claims but doesn't change the frequency of errors — you still need to catch every one.
• Automated reimbursement improvements: Amazon's automatic reimbursement system has improved, catching more lost/damaged inventory without seller intervention. However, it still misses 30-50% of eligible cases, particularly shipment discrepancies and returns not restocked.
• 18-month claim window: The window for most claim types remains 18 months from the date of the event. This is generous but sellers who audit quarterly or annually often discover claims that have already expired.
• Stricter documentation requirements: Amazon now requires more specific documentation for certain claim types, particularly inbound shipment discrepancies. Having your shipment records organized is more important than ever.

The 5 claim types in detail

1. Lost inventory

The most common and usually the highest-value claim type. Units that were received into FBA but can no longer be located — they're not in sellable, unsellable, reserved, or customer-shipped status.

Where to find it: Reports → Fulfillment → Inventory Adjustments. Filter by reason code "M" (misplaced by Amazon). Then check for a corresponding "P" (found) event within the same ASIN and timeframe. If no matching "P" event exists within 30 days, the unit is eligible for a reimbursement claim.

What you need: Adjustment ID, FNSKU/ASIN, date of adjustment, quantity, and your calculated product value.

Expected recovery: Amazon reimburses based on a formula using your average selling price, minus fees. Typical recovery per unit is 50-70% of your selling price.

2. Damaged by Amazon

Units that were damaged while in Amazon's possession — during receiving, storage, or fulfillment. This specifically covers Amazon-caused damage, not customer return damage.

Where to find it: Same Inventory Adjustments report. Filter for reason code "E" (damaged at warehouse). Verify the damage was Amazon-caused, not customer-caused (different reason codes).

What you need: Adjustment ID, evidence that the product was in sellable condition when received (your inbound shipment prep documentation helps here).

3. Inbound shipment discrepancies

You shipped 500 units but Amazon only received 488. The 12 missing units are your money, sitting somewhere in Amazon's system or lost in transit from dock to shelf.

Where to find it: Inventory → Shipments → select shipment → Reconcile tab. Compare "Shipped" vs "Received" quantities. Discrepancies become eligible after Amazon's 90-day investigation window closes (they may find units that were initially miscounted).

What you need: Shipment ID, product details, shipped quantity (from your records), received quantity (from Amazon), and ideally a Bill of Lading or shipping receipt showing the correct quantity was handed off to the carrier.

Pro tip: Always photograph your shipment contents and include a packing slip inside each box. This documentation is invaluable when disputing discrepancies.

4. Customer returns not restocked

A customer returns a product. Amazon receives it at the fulfillment center. But the unit is never moved back to sellable inventory, never marked as disposed, and never reimbursed to you. It simply disappears in the return processing workflow.

Where to find it: Reports → Fulfillment → FBA Customer Returns. Cross-reference with Inventory Adjustments. Look for returns where Amazon processed the refund to the customer and received the unit back, but your inventory count doesn't reflect the returned unit.

What you need: Order ID, return date, ASIN, quantity, and evidence that the return was received by Amazon but not restocked or reimbursed.

5. Fee overcharges (weight and dimension errors)

Amazon measures your products and assigns a size tier (Small Standard, Large Standard, Small Oversize, etc.) that determines your fulfillment fee. If Amazon has incorrect measurements on file, you could be paying the wrong size tier fee on every single unit sold — an ongoing overcharge that accumulates rapidly.

Where to find it: Reports → Fulfillment → Fee Preview. Compare Amazon's recorded dimensions and weight against your actual product specifications. Pay special attention to products near size tier boundaries — a product that's 15.0 inches (Large Standard) vs 14.9 inches (Small Standard) can mean a $1-3 difference in fulfillment fee per unit.

What you need: Your actual product dimensions and weight (measured accurately), Amazon's recorded values, and ideally a cubiscan request to have Amazon remeasure at the fulfillment center.

Step-by-step filing process

1. Gather documentation: Transaction IDs, shipment IDs, adjustment IDs, dates, quantities, and supporting evidence for each claim.
2. Open a case: Seller Support → Get Support → Selling on Amazon → Fulfillment by Amazon → select the specific issue type.
3. Submit claim: Include ASIN, quantity, relevant IDs, date range, and a clear description of the discrepancy. Be specific and factual — no emotional language.
4. Track the case: Note the case ID and expected response timeline. Follow up if no response within 7 business days.
5. Appeal if rejected: Many legitimate claims are initially rejected. Resubmit with additional documentation and a clear explanation of why the claim is valid.

Documentation requirements

Common rejections and appeals

Rejection: "Already reimbursed." Amazon's system sometimes shows a partial reimbursement that doesn't cover the full quantity. Check the reimbursement amount against your claim. If the quantity doesn't match, reopen with the specific discrepancy.

Rejection: "Outside reimbursement window." Verify the dates. Amazon's system sometimes miscalculates the window start date. If your claim is within 18 months of the event, provide the specific event date and request reconsideration.

Rejection: "Insufficient documentation." The most common rejection. Resubmit with all supporting documentation formatted clearly: ASIN, quantity, date, transaction ID, and a one-paragraph factual description of the discrepancy.

Rejection: "No discrepancy found." Request specific details about Amazon's investigation. Sometimes the case handler didn't review the correct report. Provide the exact report name, date range, and transaction IDs where the discrepancy appears.

How reimbursement amounts are calculated

Amazon uses a formula to determine reimbursement value. The formula considers your average selling price over the last 90 days, current selling price, and the category referral fee. The reimbursement is typically 50-70% of your selling price — less than you'd like, but still significant money that's yours by right.

For fee overcharges, Amazon corrects the fee going forward and may issue retroactive reimbursements for overcharges in the review period (typically 90 days, though you can request longer periods with documentation).

Automating the process

Manual reimbursement auditing requires downloading multiple reports, cross-referencing data across different formats, and tracking claim windows — 4-8 hours per month of detailed, tedious work. Most sellers either skip it entirely or hire a service that takes 25% of whatever they recover.

For details on the commission-free alternative, see our reimbursement commission comparison and our comprehensive FBA reimbursements guide.

How often to audit

Audit monthly at minimum. Weekly is ideal because it catches issues while documentation is fresh and well within the reimbursement window. The worst approach is annual audits — by the time you discover discrepancies, many claims have already expired.