Amazon is closing the last gap in seller-fulfilled returns. Starting December 18, 2026, US returns on seller-fulfilled orders need a prepaid return label, and you get seven calendar days per return request to provide one or refund the customer. Miss the window and Amazon can refund the buyer itself and take the money out of your account, with the item never coming back.
What happened (confirmed)
Amazon sent seller-fulfilled sellers an email signed by the Amazon Services team. PPC Land published the text on October 19, 2026, and sellers were discussing the same notice that day. The email carries no visible send date. Here is what it says:
• Starting December 18, 2026, all US returns for seller-fulfilled orders, excluding heavy and bulky items, require a prepaid return shipping label
• Address-only labels that make the customer pay return shipping will no longer meet the requirement, except temporarily for heavy and bulky items
• Within seven calendar days of a return request, you must upload a prepaid label in the Manage seller-fulfilled returns workflow or issue a full refund without requiring the item back
• If you do neither, Amazon may automatically issue a returnless refund and deduct the balance from your selling account
• Labels shared through Buyer-Seller Messaging or any channel outside the Manage Returns workflow do not count
Amazon's stated reason is a consistent process for US and international returns and a better customer experience.
This builds on February 8, 2026, when Amazon required all US sellers to use the Amazon Prepaid Return Label program regardless of item value. At the time, Amazon said category exemptions would continue, including Handmade, certified pre-owned watches, non-physical items, dangerous goods, and extra-large or heavy items.
What the notice does not answer:
• How heavy and bulky is defined, or when that temporary exception ends
• Whether the other February exemptions, like Handmade or dangerous goods, survive
• Who ultimately pays the label on buyer-fault returns, and whether automatic returnless refunds qualify for SAFE-T reimbursement
PPC Land also reported that Amazon's "Manage seller-fulfilled returns" help page, as captured October 19, had not yet been updated for the change.
Sources: Amazon Services team email to seller-fulfilled sellers, as published by PPC Land, "Amazon forces prepaid return labels on US seller orders from December 18" (October 19, 2026). Sellers Ask Sellers forum, "Seller-fulfilled returns to require prepaid labels as of Dec 18" (October 19, 2026). Amazon Seller Central News, "Prepaid return labels required for high-value items starting February 8" (2026).
Why this matters
Analysis: the label rule is not the scary part. Most US FBM returns already run on Amazon's prepaid labels. The scary part is the clock. A return request that sits in a queue for a week is no longer just slow service. It becomes a refund with no product coming back, pulled straight from your balance.
The timing makes it worse. December 18 lands in the middle of holiday returns. Last season, Amazon let purchases made November 1 through December 31, 2025 be returned until January 31, 2026. If it repeats that window, most of your holiday FBM returns will run under the new rule while your team is most stretched.
It also removes a lever. Sellers on the forums point out that telling a buyer they would pay return shipping used to stop a lot of buyer's remorse returns. Outside heavy and bulky, that lever is gone.
Who it affects most
• FBM brands shipping from their own warehouse or a 3PL
• Sellers with exempt SKUs, like Handmade or dangerous goods, who have been issuing address-only labels
• Teams that send return labels through Buyer-Seller Messaging today
• Higher-priced items, where a missed deadline means losing the sale and the inventory
• Sellers serving US customers from outside the US
What sellers should do before December 18
1. Pull the last 90 days of seller-fulfilled returns and flag every one that used an address-only label or a label sent by message. That is your real exposure.
2. Find the notification in your Seller Central account and read the linked help pages yourself. The help text was lagging the email as of October 19.
3. Give the pending returns queue a daily owner and a backup. Do not manage to day seven. Clear it every business day.
4. Set returnless refund rules by SKU. If return postage plus handling costs more than you recover, refund on purpose instead of letting Amazon do it for you.
5. Rebuild FBM margins with a return label cost baked in for every SKU, starting with your highest return rates.
6. If you sell heavy and bulky items, document how they are classified now. The exception is temporary and undefined.
7. Analysis: for high-return SKUs that are FBA-eligible, run the math on moving them into FBA, where Amazon runs the returns flow.
Our take
Amazon keeps pulling FBM toward the experience shoppers get on FBA: prepaid labels, faster refunds, no back-and-forth. That is good for conversion and hard on sellers who relied on friction to manage returns. The brands that get hurt on December 18 will not be the ones with high return rates. They will be the ones with nobody watching the queue.
If you run FBM and do not know how many of your returns still go out address-only, find out before the holiday rush. CoreTrex can audit your seller-fulfilled returns, set SKU-level refund rules that protect margin, and build a daily returns workflow so nothing ages into an automatic refund. Talk to a strategist.