Amazon FBA Prep
Prep-center requirements, FNSKU labeling, poly-bag specs, costs and the inbound defect fee.
Yes, most FBA sellers now need a prep center. Amazon discontinued its in-house FBA prep and labeling services on January 1, 2026, so every unit must arrive fully labeled, poly-bagged, and compliant. A third-party prep center applies FNSKU labels, packages to Amazon’s specs, and ships to fulfillment centers, helping you avoid inbound defect fees.
An Amazon FBA prep center is a third-party logistics (3PL) warehouse that receives, inspects, labels, and packages your products to meet Amazon’s FBA requirements before forwarding them to fulfillment centers. Services include FNSKU labeling, poly bagging, bubble wrapping, bundling, kitting, and shipment creation, ensuring inventory arrives compliant and ready to sell.
Most prep centers charge a per-unit fee for standard prep (FNSKU labeling and poly bagging), typically about $0.40 to $1.50 per unit. Pricing depends on monthly volume, product size and complexity, and add-ons like bundling, bubble wrapping, or kitting. Oversized or fragile items cost more, and many centers offer volume discounts.
An FNSKU (Fulfillment Network Stock Keeping Unit) is Amazon’s unique barcode that ties each unit to your seller account. It prevents inventory commingling with other sellers and lets Amazon track your products through FBA. Each unit needs one scannable FNSKU on a flat surface, with any manufacturer barcodes (UPC/EAN) covered.
Poly bags for FBA must be transparent and at least 1.5 mil thick, sealed, and fit snugly around the product. Any bag with a 5-inch-or-larger opening requires a printed suffocation warning. The barcode must stay scannable through or on the bag, which should not protrude more than three inches past the product.
The inbound defect fee is a penalty Amazon charges when shipments arrive with labeling errors, missing prep, or routing mistakes. As part of Amazon’s 2026 fee restructuring it rose sharply (reported around $0.32–$5.72 per unit, often near $0.60) from a few cents previously. Using a compliant prep center is the practical way to avoid it.
A prep center is a specialized 3PL focused on Amazon FBA compliance — FNSKU labeling, poly bagging, bundling, and shipping to fulfillment centers. A general 3PL handles broader fulfillment: storing inventory and picking, packing, and shipping direct-to-consumer orders across channels. Many providers do both, supporting FBA prep plus multichannel DTC fulfillment.
Bundling combines multiple products into a single sellable unit (such as a gift set), while kitting assembles components into one SKU. Both must be packaged so warehouse staff cannot separate them, labeled “Sold as set — Do not separate,” and carry a single FNSKU with internal manufacturer barcodes covered.
Yes. Most prep centers and 3PLs accept shipments directly from overseas suppliers, so products never pass through your home or office. The center receives the freight, inspects and counts units, applies FNSKU labels, prepares everything to Amazon’s specifications, and forwards compliant shipments to Amazon fulfillment centers.