How to Submit Your Own Sourcing Cost to Amazon

Amazon lost 86 units of your product in its own warehouse and paid you $2.41 each. You paid $6.00. That gap is not an error, and it is not a support failure: since the FBA inventory reimbursement policy took effect, it is the normal output of the system. Amazon pays out the sourcing cost of the unit, and unless you submit your own sourcing cost to Amazon, the figure it pays is an estimate Amazon made on your behalf.

The estimate is the part sellers miss. It is not a placeholder waiting for your invoice. It is the number that gets paid.

Why a lost unit pays less than your cost

The policy splits every loss into two cases, and they pay very differently.

Lost or damaged before a customer order. This is warehouse loss, damage in the fulfillment center, and units that vanish on the way in. Amazon pays the sourcing cost. If the unit is classified as unsellable, it pays a reduced estimated cost of the unit. Your sale price never enters the calculation.

Lost or damaged after a customer order. This is the customer return that never comes back, or comes back destroyed. Here Amazon pays the refund amount, or the sales price of the replacement item on the original order, minus applicable fees. This one tracks your revenue.

So two identical units can be paid out at very different amounts depending on which side of the order they were sitting when they disappeared. A seller who checks only the total in the report and not the reason code has no idea which rule was applied.

Amazon announced the change in the Seller Central forums with a March 10, 2025 effective date, then pushed it to March 31, 2025 after seller pushback. It has been in force ever since. Nothing about it is new. What is new, every month, is the set of sellers meeting it for the first time.

What Amazon counts as sourcing cost

Sourcing cost is your cost to source the product from a manufacturer, wholesaler or reseller, or to produce it if you are the manufacturer. That definition is narrower than your landed cost, and the exclusions are where margin disappears:

• Inbound freight is excluded.
• Customs duties are excluded.
• Handling and prep are excluded.
• Any other ancillary cost is excluded.

If you import, your real cost per unit and your sourcing cost per unit are two different numbers, and only the smaller one is payable. The policy also caps the payout at $5,000 per unit.

Amazon builds its own estimate from comparable products across Amazon, other sellers and wholesale channels. For a private label unit with no close comparable, that estimate can land anywhere. Sellers in the forums report payouts at 40% of cost, 47% of cost, and roughly one third of documented cost. Those are individual reports, not a measured average, but they all point the same way: the estimate errs low.

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How to submit your own sourcing cost to Amazon, step by step

The lever is the Manage Your Sourcing Cost page in Seller Central. The procedure, straight from the policy:

1. Open Manage Your Sourcing Cost and pull the list of ASINs with an Amazon-assigned cost. Every ASIN you sell through FBA has one, whether you have ever looked or not.
2. Compare each assigned cost against your invoice, unit cost only. Strip freight, duty and prep out before you compare, because Amazon will strip them out anyway.
3. Submit your own sourcing cost for every ASIN where the assigned figure is below your unit cost. Do this before a loss, not after one.
4. Have the documentation ready. Amazon may request documents to validate the amount you submit. A supplier invoice that shows unit cost separately from freight is the document that survives review.
5. Expect the estimate to move. The policy says Amazon periodically refreshes its cost estimates after March 31, 2025. A value you corrected in February is not corrected forever.

Do this ASIN by ASIN across the catalog once, and then only on new ASINs. It is a one-afternoon job that changes the payout on every future warehouse loss.

The 60-day window to dispute a valuation

You have 60 days after Amazon issues the payment to dispute the valuation. Sixty days from the payment, not from the loss, not from when you noticed.

That window is the reason this is a calendar problem and not a paperwork problem. Payouts land in the report without an email. If you reconcile quarterly, one paid on October 3 expires on December 2, in the middle of peak, and you will find it in January when there is nothing left to file. The same arithmetic applies to every clock a Q4 shipment opens.

There is a second limit that catches sellers mid-correction: Amazon will decline a resubmission if you already submitted and received a decision on a cost update request or a claim for the same item within the last 30 days and you have not supplied new information. "New information" is doing real work in that sentence. A second attempt with the same invoice is not a second attempt.

What other sellers report, and what is not in the policy

One report worth knowing about, and worth treating as a report: a seller describes support staff using up their monthly submission attempts on their behalf, which locked the seller out of submitting a corrected cost themselves, with senior support answering that they could not distinguish support-initiated from seller-initiated attempts and could not override the lockout.

A numeric monthly cap on submissions does not appear in the published policy text, which states the 30-day, same-item, no-new-information rule. So treat this as what other sellers report, not as the procedure. The operational takeaway holds either way: submit the corrected cost yourself, and do not ask support to do it for you. A support agent spending your attempt is a risk you can remove by never creating the case.

How to stop it happening again

• Correct sourcing cost for the whole FBA catalog now, while Q4 volume has not started generating losses.
• Re-check assigned costs after any supplier price change, and once a quarter regardless, because the estimates refresh.
• Reconcile the report monthly, on a date you actually keep. The 60-day dispute window cannot be extended.
• Read the reason code, not just the amount. Pre-order and post-order losses pay under different rules, and only one of them is worth disputing on valuation.
• Keep unit cost separate from freight and duty in your supplier invoices, so the document you submit answers the question Amazon is actually asking.

SellerKey reads your Seller Central and FBA reports and surfaces the gaps and the returns that never came back, so the 60-day window is visible while it is still open. It does not file claims on your behalf, and it does not write anything to your Amazon account.

Related reading: how long you have to file a SAFE-T claim, which prep and labeling units are no longer eligible, and what happens when Amazon changes your product dimensions and the FBA fee goes up.

#reimbursements#fba#seller central#q4

👋Hey! I'm Amara

Press at SellerKey.co

☕ Espresso. Never a latte macchiato.

I cover Amazon fee and policy changes: what changed, when it applies and where Amazon published it.

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