Amazon FBA Prep Requirements: A Practical Guide for Sellers

Amazon FBA prep requirements, in plain English

Amazon FBA prep requirements exist for one reason: Amazon's warehouses need to receive, scan, store and ship millions of items without a person stopping to figure out what each one is. If a unit can't be scanned, falls apart, leaks or splits into pieces, it slows everything down. So Amazon sets rules about how inventory should arrive.

We prep inventory for Amazon every day at our warehouse in Niles, Illinois, and the same handful of issues come up again and again. This guide covers the concepts behind them.

One important note before we start. Amazon updates these rules, and the official version lives in Seller Central. We're not going to quote specific dimensions, deadlines or policy numbers here, because they change and an outdated number is worse than none. Use this to understand the why, then confirm the details in Seller Central's help pages for your product.

Unit barcodes and FNSKU labels

Every unit you send needs a barcode that Amazon can scan and connect to your listing. For most sellers that's an FNSKU, the Amazon-specific code you generate in Seller Central for each product.

Some products can use the manufacturer barcode instead, depending on your account settings and the item. But the FNSKU is what most third-party sellers use, mainly because they keep your units tied to you and not mixed with another seller's stock of the same product.

A few general principles we see on the floor:

• Only one scannable barcode should be visible on the outside of the unit. If there's an old barcode, it usually gets covered.
• The label needs to be flat and readable. Wrapped around a curve or wrinkled over a seam, it may not scan.
• The label has to match the exact item. Color, size and pack count all matter.
• If the unit goes into a bag, the barcode needs to scan through the bag or go on the outside.

The last one gets missed a lot. Somebody labels the product, bags it, and now the barcode is behind cloudy plastic. Small thing. It can still cause a receiving problem.

Bagging, wrapping and FBA packaging basics

Not every product needs extra packaging. A sturdy retail box with a label on it is often fine. But some items clearly do, and Amazon's guidance groups them into categories.

Poly bag requirements in general

Bagging usually applies to things that can get dirty, snag or fall apart: clothing, fabric, plush toys, loose small parts, items in flimsy packaging. In general, bags need to be clear, sealed and the right size for the product, and larger bags typically carry a suffocation warning. Thickness and warning wording are spelled out in Seller Central, so check there instead of buying whatever bags are cheapest.

Bubble wrap and fragile items

Glass, ceramics, anything with sharp edges or a product that could break in a drop. The idea is that the item should survive normal handling in a fulfillment center, which is rougher than most people picture. The barcode still has to be scannable after wrapping, so it often goes on the outside.

Liquids, powders and sharp items

These have their own rules about sealing, double bagging or boxing. They're also the categories where we see the most variation by product, so read the Seller Central page for your exact item type. (Worth knowing: our warehouse has its own limits here too, like prior written approval for liquids over 2 lb.)

Sets and multi-packs

If you sell items as a set, Amazon needs them to stay together as one unit. Otherwise a warehouse worker might scan one piece and ship it on its own, and your customer gets half an order.

So sets usually get bagged, shrink-wrapped or boxed together, with a single barcode for the set on the outside. The individual barcodes on the pieces inside should be covered or not scannable. Some sellers add a "sold as set, do not separate" label too, depending on what Amazon currently asks for.

This is exactly what kitting and bundling covers on our side: assembling multi-packs and bundles before the label goes on.

Expiration-dated products

Food, supplements, cosmetics and some other categories come with expiration dates, and Amazon has rules about how dates are shown and how much shelf life an item needs when it arrives. The specifics vary by category and change from time to time, so look them up in Seller Central for your product.

Two general things matter from a warehouse point of view. The date needs to be readable on each unit (and on the carton, in some cases). And units with different dates should be kept clear so the oldest stock doesn't end up stranded.

If you need dates recorded at receiving, lot and expiry capture is something a prep center can do for you. One more note on supplements specifically: we only accept supplements with invoices from a U.S.-based manufacturer or authorized U.S. distributor.

Carton labels and shipment setup

Units go to Amazon inside cartons, and the cartons have their own requirements. Each one generally needs a shipment label generated from your shipping plan, placed where it can be scanned and not over a seam. Cartons should be in good shape, packed so contents don't shift, and within Amazon's current size and weight limits (check Seller Central for those).

Some sellers ship case-packed (each carton holds the same SKU in the same quantity), others ship mixed cartons. Which one you use is set in your shipping plan, and the physical cartons have to match it. A mismatch between what the plan says and what's in the box is one of the most common sources of inbound problems.

Bigger shipments go on pallets, which adds another layer of labeling and stacking rules.

Where a prep center fits in

None of these Amazon FBA prep requirements is hard on its own. It just adds up, especially once you have 30 SKUs and three of them need bags, one is a set and one has an expiration date.

That's why sellers hand it to a prep center. If you're not sure what that involves, start with what an FBA prep center does. On our side, Amazon FBA prep covers labels, bags, bubble wrap, case packs and pallets, and inspection and quality control catches damaged or mismatched units before they reach Amazon.

One clear boundary, though. We follow the work order and Amazon's requirements as you share them, and you stay responsible for your listings and shipping plans being correct. If something on the work order looks off, we'll ask. All add-on rates are on the pricing page.