Overview

Amazon will stop allowing commingling of FBA inventory shipped on or after March 31 2026. The policy swap replaces the shared‑stock model with strict barcode rules that differ for Brand Registry owners and for other sellers. Understanding the new requirements now is essential to avoid costly relabeling fees and shipment rejections later this year.

Key Points

• Commingle end date — All units arriving at Amazon fulfillment centers on or after 31 Mar 2026 must be tracked individually, ending the practice of mixing identical products from different sellers.
• Brand‑owner simplification — Sellers enrolled in Brand Registry can rely on the manufacturer’s UPC, EAN or ISBN and skip the Amazon‑issued FNSKU label on every unit that already bears a valid barcode.
• Reseller labeling mandate — Wholesalers, arbitrage operators and any seller not listed as a brand owner must affix an Amazon FNSKU sticker to every item, even if the product already carries a UPC or EAN.
• No‑barcode exception — Products lacking any manufacturer barcode—such as custom‑made goods, private‑label items without UPCs, or unbranded accessories—still require an Amazon FNSKU label regardless of seller type.
• Prep‑center impact — Third‑party prep services will need to adjust their SOPs by March 2026 to either stop applying FNSKUs for Brand Registry owners or to start applying them for all non‑brand sellers.
• Potential cost shift – Brand owners can cut labeling labor and sticker costs, while resellers should budget for the extra FNSKU stickers and possible increased handling time.

What’s Changing

1. Barcode selection — When creating a shipment, Brand Registry owners choose “Manufacturer barcode” in Seller Central; Amazon then verifies the UPC/EAN/ISBN and skips the FNSKU step, e.g., a 12‑oz shampoo with a UPC can be sent directly to the fulfillment center without additional stickers.
2. Mandatory FNSKU for non‑brands — Sellers without Brand Registry status must select “Amazon barcode” for every SKU; Amazon generates a unique FNSKU that must be printed and applied, for instance, a bulk pack of generic phone chargers that previously shipped with only a UPC now needs a distinct Amazon label on each unit.