FBA Prep Requirements for Shipments from China

Amazon FBA prep requirements are the packaging and labeling standards every unit has to meet before a fulfillment center accepts it. Each unit needs a scannable FNSKU barcode label, protective packaging suited to its category, and master cartons that stay inside Amazon's weight and size limits. Miss any of those and the shipment gets rejected or charged per-unit fees.

As of 2026, there is no fallback at the warehouse. Amazon ended all of its US prep and labeling services on January 1, 2026, so inventory that arrives unprepped no longer gets fixed after arrival. If you source from China, every detail has to be right before the container closes.

That is why this guide starts at the factory, not the fulfillment center. At CN Ally, where we run FBA prep on China-sourced shipments, the pattern is consistent: sellers who clear Amazon receiving on the first attempt wrote the prep spec into their factory order. Sellers who struggle treated prep as something that happens later. Below is the full checklist of what Amazon requires, what to specify in China, and how to verify it before you ship.

What Amazon Actually Checks When Your Shipment Arrives

Receiving checks three things: that every unit carries the right label, that every unit is packaged to survive the warehouse, and that every carton matches your shipping plan. Everything below falls into one of those buckets.

Unit labeling. The FNSKU (Fulfillment Network Stock Keeping Unit) is the barcode that ties your inventory to your seller account. Prep guides tracking the 2026 FBA prep rules describe the standard this way: print at 300 DPI in Code 128 format, keep at least 80 percent contrast, leave a 1/8-inch white quiet zone around the barcode, and use the standard 1-by-2-inch label (1 by 3 is preferred). Place the label on a flat surface of the outer packaging, never over a seam, fold, or edge that compresses in transit. If the product already shows a manufacturer barcode, cover it completely, either by placing the FNSKU directly over it or with an opaque sticker first. Amazon's scanners must see exactly one barcode.

One 2026 detail worth knowing: sellers enrolled in Brand Registry and acting as the brand representative can generally keep using manufacturer barcodes (UPC, EAN, ISBN). Everyone else reportedly needs an FNSKU on every unit following a March 2026 rule change. Confirm your exact status in Seller Central before you lock in a labeling plan.

Unit packaging. The packaging rules depend on the product category. The table below covers the categories that generate most receiving problems, drawn from category-level prep breakdowns published by prep providers.

Category · What Amazon expects

• Apparel and textiles: Individual transparent polybag with suffocation warning; size tag visible through the bag; FNSKU on the flat exterior of the bag
• Plush toys, small parts, items that shed dust: Polybag at least 1.5 mil thick, fully sealed
• Glass, ceramics, fragile items: Full bubble-wrap coverage with bubbles facing inward; must survive a 3-foot drop; barcode scannable without unwrapping
• Liquids (non-glass): Double-sealed; sealed leak-proof polybag; outer packaging marked "LIQUID"
• Electronics: Anti-static protection plus corner protection
• Sharp or pointed items: All exposed edges covered with bubble wrap or a box
• Bundles and sets: Components shrink-wrapped or banded together; "Sold as Set" or "Do not separate" label on the outside; all inner barcodes covered
• Books and media: Moisture protection and corner protection
• Food, supplements, cosmetics with expiry dates: Expiry date printed clearly on each unit

Amazon requires transparent bags at least 1.5 mil thick, completely sealed, for apparel, plush, small parts, and anything that sheds fibers. Any bag with an opening of 5 inches or more needs a suffocation warning printed on it, legible and in English at minimum. Fit matters too: a bag that is too loose tears open in the warehouse, and a bag that is too tight distorts the label and fails the scan.

The 2026 Changes That Moved Prep to Your Side of the Ocean

Two reported 2026 changes rewrote the economics of FBA prep. First, Amazon discontinued all prep and item labeling services in US fulfillment centers effective January 1, 2026: no more FNSKU application, polybagging, bubble wrapping, bundling, or kitting at the warehouse, across every inbound flow. Second, prep-industry guides report that starting March 31, 2026, resellers not enrolled in Brand Registry must use FNSKU barcodes on all FBA inventory, removing the old flexibility around manufacturer UPCs. Both are widely reported across prep-provider guides; treat Seller Central as the final word, since Amazon's rules shift.

The practical effect: no paid safety net remains at the fulfillment center, and enforcement has tightened, with per-unit non-compliance fees widely reported in the low single dollars. The work moves upstream to wherever goods are packed. For China-sourced inventory, that means the factory floor or a China-side prep partner.

Writing the Prep Spec Into Your Factory Order

Factories do not know Amazon's rules, and "prepare for Amazon FBA" means nothing to a production manager. Your purchase order has to spell out every prep step in physical terms: materials, sizes, artwork, and placement. Here is what belongs in the spec.

FNSKU label files. Generate the labels in Seller Central (Manage Inventory, then Print Item Labels) and send the PDF to the factory. Specify the label size and attach a photo or diagram showing exactly where it goes on the packaging. Then ask how they print. Many factories only have inkjet printers, and inkjet barcodes smudge in warehouse conditions, which is an instant scanning failure. If the factory cannot print clean 300 DPI thermal labels, ship pre-printed labels to them or have a prep partner apply them.

Polybag specification. State the thickness (1.5 mil minimum), transparency, exact dimensions, and whether the suffocation warning must be pre-printed on the bag. State the seal method: heat seal or self-adhesive, fully closed. "Polybag it" is not a spec. "1.5 mil transparent polybag, 12 by 15 inches, pre-printed suffocation warning, heat sealed" is a spec.

Suffocation warning artwork. Provide the exact warning text yourself. Do not let the factory write English safety warnings on its own; wording errors are common and Amazon rejects bags with missing or incorrect warnings.

Bundle and set assembly. For multi-packs, attach a one-page drawing: which items go together, how they are bound (shrink wrap, bands, or a rigid box), where the "Sold as Set" label goes, and confirmation that every inner manufacturer barcode is covered. The exterior FNSKU must be the only barcode a scanner can see.

Carton rules. Cap the weight and dimensions in the order (more on the exact limits below), require new corrugated boxes only, and state whether SKUs may share a carton. If your shipping plan is created before packing, send the 4-by-6-inch box ID labels with placement instructions: flat, on the top and one side of each box.

The table below maps each spec line to what happens when it is vague.

Spec line · Write this · What goes wrong if you skip it

• FNSKU file plus placement diagram: Label size, 300 DPI, exact placement photo · Labels land on seams and fail scanning; relabeling fees
• Polybag thickness and size: Exact mil, dimensions, pre-printed warning, seal method · Rejected for thin bags or missing warnings
• Warning artwork: Attach the exact text · Factory-written warnings get the wording wrong
• Bundle assembly drawing: Item list, binding method, label position · Sets arrive separable and Amazon splits them
• Carton caps: Max weight, max side length, new boxes only · Overweight or oversize fees, possible refusal
• Inner barcode coverage: Cover every manufacturer barcode with an opaque sticker · Scanner confusion and misrouted inventory

One communication habit prevents most of this: send the spec in writing with pictures, then ask the factory to photograph one fully prepped unit before mass packing starts. One photo of a correctly prepped unit is worth three pages of instructions, and it gives your inspector a reference to check against.

The Carton Rules Most Sellers Discover Too Late

Unit prep gets the attention, but carton mistakes cause a surprising share of receiving problems. Amazon's box limits are hard limits, not guidelines.

Amazon enforces a 50-pound maximum per standard box, dropping to 25 pounds for non-conveyable items, and no single side may exceed 25 inches. Use a calibrated scale and a tape measure; estimating is how overweight fees happen. Boxes must be new, sturdy corrugated cartons capable of surviving stacking. Damaged, previously used, or weak boxes get refused at the dock.

Generate the FBA box ID labels in Seller Central, print them at 4 by 6 inches, and apply them flat to the top and one side of each box. Completely remove or cover every old shipping label, tracking number, or barcode; conflicting barcodes cause scanners to misroute your inventory. Finally, the shipping plan must match the physical contents exactly: any discrepancy triggers manual verification delays and fees.

Verifying Prep Before the Container Closes

Prep errors are cheap to fix at the factory and expensive to fix anywhere else, so build a prep check into your pre-shipment inspection. The checkpoints are straightforward:

• Pull cartons at random and scan 10 to 20 FNSKU labels with a phone scanner. Every one must read on the first attempt.
• Check placement: labels on flat surfaces, never on seams, with manufacturer barcodes fully covered.
• Confirm polybag specs: correct thickness, fully sealed bags, suffocation warnings present and legible.
• Test bundle integrity: try to pull a set apart. Confirm the "Sold as Set" labels are on the outside.
• Weigh a sample of cartons and measure their sides against the limits.
• Compare box ID labels against the shipping plan, carton by carton.
• Keep one fully prepped unit as your reference sample and photograph it. Your inspector compares production output against that unit, not against a written description.

This is the same visit where quantity and workmanship get checked, so it adds little cost. Our walkthrough of pre-shipment inspection in China shows how to fold prep verification into a standard QC appointment.

The shipment workflow: from factory floor to fulfillment center

Prep is one step in a chain, and the chain breaks at handoffs. Here is how the pieces fit in order.

First, the factory produces and preps: units labeled with FNSKU, polybagged where required, bundled per your spec, packed into Amazon-compliant cartons. This is where the prep spec you wrote into the order gets executed, and where your pre-shipment inspection verifies it.

Second, cartons move to the forwarder, either to a China-side consolidation warehouse or directly into a container. If you are shipping LCL or combining suppliers, this is where mixed cartons get sorted and the shipment is built. Your forwarder needs the FBA shipment plan: which fulfillment center, how many cartons, and the Amazon shipment ID.

Third, the forwarder books the Amazon delivery appointment. Amazon receiving works on appointments, not walk-ins; a truck that arrives without one waits or gets turned away. The forwarder or their US partner handles this, but they can only do it with accurate carton counts and the shipment ID you provide.

Fourth, Amazon receives, checks, and stows. If prep is right, your inventory goes live within days. If it is wrong, you get the defect notice and the choice between fixing it at Amazon's rates or having it sent back. Every step upstream exists to avoid that moment.

What Fixing Prep Costs in China vs. After Arrival

Every prep task has a price at each stage, and the price climbs the further the goods travel. Third-party sourcing guides publish China-side benchmarks that make the comparison concrete:

Prep task · Typical China cost per unit (reported benchmark)

• FNSKU labeling: $0.05-0.15
• Polybagging: $0.08-0.20
• Bubble wrap: $0.10-0.30
• Bundle, 2-pack or 3-pack: $0.20-0.50
• Insert or thank-you card: $0.05-0.15
• Box content label: $0.10-0.20

On a basic product, full China-side prep reportedly runs about $0.25 to $0.50 per unit, versus $0.80 to $1.50 at a US prep center. On 5,000 units, that gap is several thousand dollars.

The other side is what non-compliance costs: prep-industry guides report per-unit chargebacks of roughly $0.50 to $2 or more on non-compliant inventory, plus delays and stranded stock. Catching a missing suffocation warning at the factory costs pennies per bag. Catching it at the fulfillment center costs the whole shipment's timeline. Treat the figures above as planning benchmarks from third-party guides, not quotes; your product and volumes set the real numbers.

Frequently Asked Questions

Can my Chinese supplier do FBA prep for me?

Yes for simple tasks: FNSKU labeling and polybagging are well within a factory's ability if you give an exact written spec with placement photos. Verify the output during inspection, since factories are inconsistent at small-detail work. Complex bundling, kitting, or multi-SKU assembly usually belongs with a dedicated China prep partner.

Do all products need polybags for Amazon FBA?

No. Polybags are required for categories that need containment or protection: apparel, plush toys, small parts, and items that shed dust or fibers. A sturdy product in a solid retail box generally does not need one. Skip the bag-everything-by-default habit; unnecessary bagging adds cost and another failure point.

What happens if my shipment fails FBA prep requirements?

The shipment gets rejected at receiving, hit with per-unit non-compliance fees, or left as stranded inventory while you arrange rework. Since January 2026, Amazon no longer offers prep services at US fulfillment centers, so there is no paid option to have the warehouse fix it. The goods either go to a prep center at your expense or come back.

Should the supplier print FNSKU labels, or should I send them?

Generate the labels in Seller Central and send the PDF, or ship pre-printed labels, rather than relying on the factory's printer. Most factories run inkjets, and inkjet barcodes smudge enough to fail scanning. Thermal printing at 300 DPI is the reliable route, wherever it happens.

Do I still need FNSKU labels if my product already has a UPC?

If you are the Brand Registry brand representative, manufacturer barcodes are generally accepted. For everyone else, prep guides report FNSKU became mandatory on all FBA inventory after March 31, 2026. Confirm in Seller Central; this is one of the rules Amazon has actually been changing.

Does Amazon still offer prep services for FBA?

No. Amazon discontinued all prep and item labeling services in US fulfillment centers effective January 1, 2026, across every inbound flow. All labeling, polybagging, bundling, and protective packaging has to happen before the shipment reaches the fulfillment center.

What is an Amazon shipment ID, and when do I create it?

The shipment ID is Amazon's identifier for your inbound shipment, created in Seller Central when you build the shipping plan. Your forwarder needs it to book the delivery appointment and to label the shipment correctly. Create the plan as soon as carton counts are confirmed, not after the goods are already on the water; a missing shipment ID is a common reason deliveries get delayed at the fulfillment center.

Make Prep Part of the Order, Not Part of the Warehouse

The decision rule is straightforward. If the product is simple (one SKU, label plus polybag) and the factory has been audited, have the factory prep to your written spec and verify it during inspection. If the shipment involves bundles, fragile goods, multiple SKUs, or a factory you have not worked with before, route it through a China prep partner or your sourcing agent's prep line before the forwarder collects the cartons. If the goods are already in the US, a domestic prep center works, but budget roughly two to three times the China per-unit cost.

Whichever route you take, the principle is the same: prep is a line item in the purchase order, with a spec sheet and a photo-verified reference unit, not a task you hope someone handles downstream. Get that right and Amazon receiving becomes a non-event, which is exactly what it should be.

Pair this checklist with our China-to-FBA freight guide to plan the shipping side, and if you want prep, inspection, and freight handled as one China-side workflow, CN Ally's Amazon FBA prep service covers labeling, polybagging, bundling, and carton compliance before your shipment leaves origin. Write to hi@cnally.com with your product details for a quote.