Amazon FBA Reimbursements in 2026: How to Document, File, and Recover What Amazon Owes You

Amazon FBA sellers are collectively losing money on a scale that most of them never see. A March 2025 Forbes report, citing reimbursement industry data, put the annual collective loss in the billions - inventory that went missing, units that arrived short at Amazon receiving, customer returns that were never restocked, and fees charged on measurements Amazon got wrong. Most of that money is never claimed. Then, on March 31, 2025, Amazon changed how it calculates reimbursements, cutting average payouts dramatically by switching from selling price to manufacturing cost as the basis for every claim. The sellers who recover the most in 2026 are the ones who understand both how to file and what to prepare before a shipment ever ships. This guide starts with the preparation - the part nearly every other resource skips.

The Scale of What Sellers Are Losing

Industry auditing firms consistently find that the typical FBA seller loses a low single-digit percentage of annual revenue to inventory errors that qualify for reimbursement but are never recovered. On a business generating meaningful FBA revenue, that figure is not a rounding error. It is an operating cost hiding in a spreadsheet column that nobody opened.

The money goes unclaimed for a few compounding reasons. Amazon does automatically reimburse sellers for some loss events, which creates a false sense that all qualifying losses are being caught. They are not. Inbound shipment discrepancies - cases where fewer units arrive at Amazon than were shipped - rarely trigger automatic payouts. Incorrect FBA fee charges based on wrong weight or dimension measurements do not either. Both categories require manual action, and both have separate filing paths from the main reimbursement portal most sellers know about.

A second reason is simpler: many sellers who do know about the filing process have never set up the key field that determines how much any approved claim pays out. Amazon calculates reimbursements based on your entered manufacturing cost. If that field is blank, Amazon estimates it. That estimate runs low, and every future payout is capped before any claim is reviewed.

The March 2025 Policy Change: Manufacturing Cost vs. Selling Price

Before March 31, 2025, Amazon calculated reimbursements using the item's selling price. After that date, the calculation shifted to what Amazon calls manufacturing cost - defined explicitly as the cost to source the product from a manufacturer, wholesaler, or reseller. Amazon's definition excludes shipping costs, handling charges, and customs duties from this figure.

The real-world consequence has been a significant drop in per-claim payouts. Sellers report that their reimbursements fell dramatically after the change - in many cases by more than half - because manufacturing cost is often a fraction of what the item sells for. For private label sellers or anyone with meaningful product margins, the gap between sourcing cost and retail price is wide, and reimbursements now reflect only the lower number.

There is one lever sellers control directly: the Manage Your Sourcing Cost page inside the IDR portal. This is where you enter your per-SKU manufacturing cost, which becomes the floor for any approved payout on that ASIN. How to set it up is covered in the section below.

Seven Claim Types Across the FBA Lifecycle

Reimbursable losses occur at different stages of the FBA process. Understanding where each type originates helps you spot them in reports and route them through the correct filing channel.

• Inbound shipment discrepancies - Units you shipped versus units Amazon recorded as received. This is the single largest category of recoverable money identified by third-party auditing firms, accounting for nearly four in ten reimbursement dollars they find.
• Warehouse-lost inventory - Units confirmed received at a fulfillment center but later recorded as missing within the network.
• Amazon-damaged inventory - Units damaged by Amazon personnel or equipment during storage, picking, or internal handling - not by customers.
• Unauthorized disposals - Units disposed of by Amazon without seller authorization or proper process.
• Units lost in customer-return transit - The buyer initiated a return and received a refund or replacement, but the unit never made it back to a fulfillment center.
• Refunds issued, item never returned - Amazon refunded the customer but the return was not completed or the item was not restocked.
• Incorrect FBA fee charges - Amazon measured a unit's weight or dimensions incorrectly and overcharged fulfillment fees. This requires a separate remeasure request and has its own look-back window - verify the current period in Amazon's FBA fee policy documentation.

Each type is separately recoverable. Each requires different documentation and, in several cases, a different filing path than the others.

The IDR Portal: What It Shows and What It Does Not

The Inventory Defect and Reimbursement portal, accessible in Seller Central under Inventory, is where Amazon surfaces most reimbursable warehouse events. The portal organizes claims into three tabs: Eligible for Claim (events Amazon has flagged as potentially payable and waiting for seller action), In Progress (filed claims under review), and Resolved (completed claims, both approved and denied).

The IDR portal is the correct place to act on warehouse-lost inventory, Amazon-damaged inventory, customer-return issues, and similar in-fulfillment-center events. It does not include inbound shipment discrepancies.

The prep center is where reimbursement evidence is created or lost permanently. Every unit that ships to Amazon without a documented count and condition record is a unit you cannot fully defend if Amazon's receiving record disagrees with yours.

Inbound discrepancy claims must be filed through a Seller Central support case, referencing the specific shipment ID and attaching documentation. Sellers who search the IDR portal for a missing inbound unit count will not find it there, even when the discrepancy is clearly documented in their shipment records. The portal does not show inbound events. Missing this distinction means missing the claim entirely, because the filing path is different and the clock runs separately.

Resolution timelines for inbound discrepancy cases typically run from a few days for straightforward unit-count mismatches to several weeks for cases where Amazon must trace inventory movement across fulfillment center transfers.

Claim Deadlines by Type

Missing a claim window means losing the recovery permanently. The windows vary enough by category that sellers who treat them all the same routinely forfeit money they could have claimed. Verify the exact current timeframes in Seller Central's FBA help documentation - these windows reflect Amazon's current policy and are subject to change.

Claim Type	Where Loss Occurs	Filing Path	Relative Window
Inbound shipment discrepancy	Amazon receiving	Seller Central support case	Longest - months after shipment closes; verify current limit
Warehouse-lost inventory	FC storage	IDR portal	Short - weeks from event date; verify current limit
Amazon-damaged inventory	FC storage or handling	IDR portal	Short - same window as warehouse-lost; verify current limit
Return lost in transit or never returned	Returns process	IDR portal	Medium - verify current window from refund date
Return received damaged by Amazon	Returns process	IDR portal	Medium - same window; reimbursed at roughly half sourcing cost
FBA fee overcharge (weight or dimensions)	Any fulfillment transaction	Seller Central support case + remeasure request	Separate window - check Amazon's FBA fee policy for current period

Third-party auditing services typically have access to a longer historical look-back than the self-service IDR portal options. If you have not audited your account in an extended period, an older window may still be open - but only until it is not.

Documentation That Gets Approved vs. Documentation That Gets Denied

What a Compliant Invoice Must Contain

Amazon's invoice requirements for claim documentation are specific and consistently enforced. A formal invoice that will pass review must include all of the following:

• Supplier full legal name and address
• Buyer full legal name and address
• Product names that correspond to the ASIN inventory being claimed
• Quantities purchased
• Unit cost per product
• Purchase date

Amazon explicitly rejects screenshots of supplier websites, PayPal transaction summaries, credit card statements, and order confirmation emails. These documents do not carry the supplier-verified fields Amazon's review process requires. A claim filed with any of them as the primary documentation will be denied. The harder consequence is that sellers often cannot refile with corrected documentation if the claim window has expired in the interim.

Why Photos Must Come Before the Box Is Sealed

For inbound discrepancy and damage claims, photos establish unit count and condition at the moment of shipping. A photo taken after the shipment arrives at Amazon shows nothing about what was inside when it left the origin facility. A photo taken at the prep center - units laid out and counted, shipment ID visible, condition evident - creates a verifiable record tied to a specific point in the chain before Amazon received the goods.

Sellers typically discover this gap only after a claim is denied. By then, the shipment has moved through the fulfillment center network, the units are intermingled with other stock, and reconstructing the original count from the seller's side is not possible.

The Pre-Shipment Documentation Window

The prep center is the place where inbound discrepancy claims are won or lost, and most sellers treat it only as a logistics step. What happens at the prep facility - before the pallet ships - determines what evidence exists when Amazon's unit count does not match the seller's.

A professionally run prep center produces documentation as part of its standard workflow: a receiving report when inventory arrives at the facility, a unit count verified against the purchase order, an inspection record noting condition at the time of prep, FNSKU label confirmation tied to specific ASINs, and photos of units before boxing. These are not just operational notes. They are the evidence that can support a reimbursement claim months after a discrepancy is discovered.

When working with a prep center, confirm what records they produce, how long they retain them, and whether they can provide photos and reports on request after a shipment has shipped. At minimum, request the following before any shipment leaves the prep facility:

• A packing list with exact unit counts per ASIN per carton
• Pre-boxing photos with the Amazon shipment ID visible in frame
• A condition inspection note for any units with visible issues at time of prep
• A confirmed handoff record when the freight carrier picks up

Combine that documentation with a copy of the Bill of Lading from the carrier. The combination establishes a chain of custody from the prep facility to Amazon's dock. When Amazon records fewer units than you shipped, that chain is your claim - without it, the discrepancy is your word against Amazon's scan data.

Setting Up Manage Your Sourcing Cost

The Manage Your Sourcing Cost page inside the IDR portal sets the per-SKU cost Amazon uses to calculate every reimbursement for that ASIN. Set this up for every active SKU before a loss event occurs. The process:

1. Open Seller Central and navigate to Inventory, then select Inventory Defect and Reimbursement.
2. Inside the IDR portal, locate the Manage Your Sourcing Cost option.
3. For large catalogs, download the bulk template; for smaller catalogs, enter costs individually through the portal interface.
4. Enter the per-unit cost as it appears on your supplier invoices - the amount actually paid to the supplier per unit, not including freight, customs, or prep fees.
5. Submit and confirm the update; Amazon will apply entered costs to future reimbursement calculations for those SKUs.
6. Set a calendar reminder to review and update costs quarterly, or whenever supplier pricing changes significantly.

Keep the corresponding supplier invoices organized and accessible. Amazon may request them to verify the entered cost when a claim is filed, and the figure on the invoice should match what is in the portal.

DIY Auditing vs. Third-Party Services

Third-party reimbursement services review your FBA account, identify eligible claims, and file on your behalf in exchange for a portion of what they recover - commonly somewhere between a fifth and a quarter of the total, varying by service and volume. After the March 2025 manufacturing-cost change reduced per-claim payout amounts, that share comes out of an already smaller pool. The math for using these services has changed.

The decision rests on two variables: how consistently you can run your own audits, and how much recoverable money you realistically have sitting unfiled.

Sellers with a manageable SKU count and the capacity to review IDR reports monthly, cross-reference shipment reconciliation reports, and open support cases when discrepancies appear will generally retain more of their recovery by handling it internally. The workflow is learnable, and the reports Amazon provides are navigable once you understand what to look for.

Sellers with large catalogs, high inbound shipment volume, or no dedicated operations staff often find that a third-party service captures claims they would have missed entirely - which justifies the fee only when the service is finding incremental recoveries, not filing claims the seller would have found anyway. One clear case for a one-time professional audit: if you have not reviewed your account in a year or more, a focused audit may surface recoverable funds before the claim windows close, after which you can evaluate whether to continue the service or move the process in-house.

Frequently Asked Questions

Where do I file an inbound shipment discrepancy claim?

Through a Seller Central support case, not the IDR portal. Reference your shipment ID in the case and attach your packing list, pre-shipment photos, Bill of Lading, and supplier invoice. Amazon does not surface inbound discrepancies in the IDR portal regardless of how clearly the shortfall appears in your shipment records - which means sellers who look only there will miss the filing path entirely.

What happens if I never entered my sourcing cost in Amazon's system?

Amazon estimates it. Enter your actual costs through the Manage Your Sourcing Cost page in the IDR portal to protect future claims. Claims already resolved and paid cannot be reopened based on a retroactive update.

Does Amazon reimburse the full sourcing cost when a customer return comes back damaged?

No. When a returned item arrives at Amazon damaged, Amazon classifies it as no longer new and reimburses at a reduced rate - roughly half of the sourcing cost rather than the full amount. This is a separate calculation from what applies to warehouse-lost or Amazon-damaged inventory, where the full manufacturing cost is the basis. Check Amazon's current returns reimbursement policy for the exact current rate, as this figure is subject to change.

How far back can I file for inbound discrepancy claims?

The inbound discrepancy window is the longest of the main claim categories, running from the date the relevant shipment closes in Seller Central. Verify the exact current period in Amazon's FBA policy documentation before filing - the window has been adjusted before, and claims after it closes are permanently ineligible.

Can I recover money if Amazon charged me incorrect FBA fees due to wrong measurements?

Yes. File through a Seller Central support case with a remeasure request. If the remeasure confirms your actual specs, Amazon refunds overcharged fees back through the applicable look-back window. To identify candidates, compare your products' actual dimensions and weight against what Amazon has on record - ASINs where those figures diverge are the ones worth pursuing. Check the current FBA fee policy for the specific period this category covers, as it differs from the inventory claim windows.

What is the difference between claims in the Eligible for Claim tab and claims I file manually?

The Eligible for Claim tab shows events Amazon has already identified as potentially reimbursable and flagged for seller action - working these is faster because Amazon has already acknowledged the loss event. Manual claims, particularly for inbound discrepancies and fee overcharges, require you to identify the issue yourself, gather documentation, and open a support case. A large portion of the highest-value claims - especially inbound discrepancies - never appear in the Eligible for Claim tab at all, which is why relying solely on that tab leaves money unfiled.