If you sell on Amazon and you are building an inbound shipment this week, this is the list to work through before anything gets taped shut. Amazon FBA prep requirements cover barcodes, bagging, bundling, carton limits and pallet build, and since the start of 2026 there is no safety net waiting for you at the fulfillment center. Work through this page and you will know what every unit needs, what your specific product category adds on top, and which parts you can hand to a supplier without regretting it.
FBA means Fulfillment by Amazon, the program where Amazon stores your inventory and ships it to customers. Prep is everything that has to happen to a unit before it arrives at one of their buildings.
What changed on January 1, 2026
Amazon confirmed on its own seller forums that from January 1, 2026 it no longer offers prep and item labeling services for FBA shipments in the US store, and that the change applies to inventory sent directly into FBA as well as inventory coming through Amazon Warehousing and Distribution (AWD), Amazon Global Logistics (AGL), Amazon SEND and Supply Chain Portal when that inventory goes through FBA.
Two details from that announcement matter more than the headline. Shipments created before January 1 were still prepped by Amazon even if the inventory landed after that date. Shipments created after January 1 that arrive without proper prep and item labeling are not eligible for reimbursement if the units are damaged or untraceable.
Read that second line again. It is not only about rejection. A badly labeled unit that gets lost inside the network is now your loss, not Amazon’s. That is the real cost of skipping a step, and it shows up months later on a reconciliation you were not expecting to run.
If you want the operator’s view of how sellers adapted, we wrote about what changed in the six months after Amazon stopped prepping inventory. If you would rather hand the whole job to someone with a prep bench and a thermal printer, that is what our FBA prep services exist for.
The five things every FBA unit needs
Before any category-specific rule applies, every single unit has to clear these five. Amazon states the general requirements plainly: each unit must have an exterior scannable barcode, or a label that includes a scannable barcode, with easily readable and accessible numbers, and any FNSKU you use must be unique and correspond to one unique product, so each variation such as size or color needs a different FNSKU.
| Requirement | What Amazon expects | Where it usually fails |
|---|---|---|
| One scannable barcode | An exterior barcode with readable digits, accessible without opening the unit | Label applied under shrink wrap, or on a curved surface that will not scan |
| One identity per unit | A different FNSKU for every size, color and variation | One FNSKU printed for a whole PO covering three colorways |
| No competing barcodes | Existing scannable barcodes removed, covered or rendered unscannable, for example with opaque tape or a black marker | Supplier’s UPC still readable next to the FNSKU |
| Contained in one package | Each unit contained within a single secure package, with no multi-piece assembly required | A two-part product shipped as two loose pieces in one carton |
| Protected for the network | Packaging that survives receiving, stocking, picking and outbound packing | Retail box with an open window and nothing over it |
Amazon is explicit about what happens when a unit misses: they may refuse, return or repackage any product delivered with inadequate or non-compliant packaging at your expense.
FNSKU labeling
The FNSKU, short for Fulfillment Network Stock Keeping Unit, is the barcode that ties a physical unit to your seller account. It is generated in Seller Central against your listing, not by your factory.
Three rules govern it. Every variation gets its own code. The code has to scan on the outside of whatever Amazon’s associate is holding. And no other barcode on that surface can scan.
That last point is the one suppliers get wrong most often. If a manufacturer’s UPC is printed on the retail box, cover it. An opaque sticker underneath the FNSKU works. A black marker across the bars works. A translucent label over a printed barcode does not, because the scanner can still read through it under bright light.
On placement, here is how we do it on our floor rather than what Amazon mandates. Labels go on a flat panel, never across a seam, a fold, a corner or a heat-shrink ridge, because those surfaces compress in transit and the bars distort. Bubble-wrapped units get bagged or boxed first, then labeled on the smooth outer layer. Anything with no flat surface at all, a rolled item or a curved bottle, goes into a poly bag and the label goes on the bag.
Print where the bars stay crisp. A thermal transfer printer at 300 dots per inch is the workhorse. Inkjet smears in a hot trailer crossing the Inland Empire in August, and a smeared label is an unscannable label.
Poly bagging and the suffocation warning
This is the single most enforced prep rule and the one that generates the most surprise. Amazon staff have set out the requirements directly on the seller forums: the poly bag must be completely sealed even when the product is already inside a sealed retail box, a suffocation warning label is required if the bag opening is 5 inches or larger measured when flat, the warning must be printed on the bag or attached as a label in a prominent legible location, bags with an opening under 5 inches do not need the warning, the bag must be a minimum of 1.5 mils thick, it must be transparent rather than opaque, and it must have a scannable barcode visible through the bag or an FNSKU label applied on the outside. The same guidance notes that the bag must not protrude more than 3 inches past the product dimensions.
| Spec | Requirement |
|---|---|
| Thickness | Minimum 1.5 mil |
| Clarity | Transparent, so the barcode reads through it |
| Seal | Fully sealed, even over sealed retail packaging |
| Suffocation warning | Required at 5 inch opening or larger, measured flat |
| Excess material | No more than 3 inches beyond the product |
| Barcode | Scannable through the bag, or FNSKU on the bag exterior |
The practical fix is boring and cheap. Buy bags with the warning pre-printed, in the sizes your catalog actually needs, and stop applying warning stickers by hand. Hand-applied stickers fall off, land crooked over the barcode, and cost more in labor than the pre-printed bag costs in material.
[VERIFY: minimum print size for the suffocation warning by bag dimension. Multiple secondary sources publish a 10 to 24 point scale tied to bag length plus width. We could not confirm the current scale against an Amazon-owned page in this session, so it is left out of the table above rather than guessed.]
Bundles, multipacks and sold-as-set
A bundle is two or more items you sell as one listing under one FNSKU. Amazon’s receiving process is built to break apart anything that looks separable, so the whole job is making the unit look and behave like one thing.
Amazon’s own guidance covers the labeling language: products that are not an official set but sold as one, such as a set of toy cars sold as a single unit, need to be packaged together and marked as a set on the outside of the packaging, with a label clearly stating that the products are to be received and sold as a single unit. Recommended phrases include “Sold as Set”, “Ready to Ship” and “This is a Set, do not separate.”
Shrink wrap or band the components together so they cannot separate under handling. Cover every interior barcode. One FNSKU goes on the outside of the finished bundle.
There is a distinction here that trips up a lot of sellers, and Amazon draws it clearly. Individual products are packaged and shipped in the same box but are not sold as a set, often differing in SKU, quantity or condition. Case-packed products are packaged and shipped in the same box with matching SKUs, matching conditions and equal quantities, usually packed that way by the manufacturer. An Amazon representative answering a seller in that same thread added the practical consequence: if items are case packed together in a single box where it is clear they are a single unit, the sold-as-set sticker is not needed, and one FNSKU on the exterior of the inner box is correct.
Loose, soft and unenclosed products
Apparel, textiles, plush and anything with a loose sleeve or pouch fall here, and this is the category that generates the most rework on our benches.
Amazon’s stated requirements: units that are not contained in secure packaging, such as loose sleeves or pouches, must be bagged or secured with a non-adhesive band or removable tape, and all footwear must be packed with no footwear material exposed, either in shoe boxes or poly bags.
Note the word non-adhesive. Tape directly onto fabric, leather or a printed finish leaves residue or lifts the surface when it comes off, and the unit becomes unsellable. That is a customer return waiting to happen, which is worse than a rejection because it lands on your account health rather than your inbound plan.
Prep by product type
Amazon assigns prep categories per ASIN, and the requirements stack. A shampoo and conditioner sold as a set has to satisfy the liquid rules and the set rules at the same time. The table below is a working starting point, not a substitute for checking your own listing.
| Product type | Typical prep |
|---|---|
| Fragile or glass | Bubble wrap with full coverage, often an outer box, then label the smooth outer surface |
| Liquids and gels | Sealed primary container, then bagged so a leak cannot reach neighbouring inventory |
| Apparel, textiles, plush | Sealed transparent poly bag with the warning where the opening qualifies |
| Sharp items | Fully contained so no edge or point can reach a hand through the packaging |
| Adult products | Opaque bagging so the contents are not visible |
| Powders and pellets | Sealed and bagged against spill |
| Small items | Bagged or boxed so they cannot be lost inside a tote |
| Sets and bundles | Banded or wrapped as one unit, interior barcodes covered, set label applied |
[VERIFY: the exact prep-category thresholds, including the packaging-cutout dimension that triggers bagging on children’s products and the current list of categories. Amazon publishes these on the Packaging and prep requirements help page, which is behind a crawl block, so confirm each line against your own Seller Central account.]
Build the per-ASIN check into your process. Open the product in Seller Central, read the prep guidance attached to that listing, and prep to what the listing says rather than what the category implies. Two products that look identical to you can carry different prep flags.
Expiration-dated inventory
If your product is consumed, applied to a body, or loses effectiveness over time, Amazon treats it as expiration-dated whether or not a date is printed on it. Amazon’s guidance states that any product with a shelf life, or that loses effectiveness with time, is subject to expiration even when no expiration date is shown on the packaging, that units must arrive at the fulfillment center with enough remaining shelf life for the product to be consumed or used plus an additional 90 days, and that perishable items are not accepted. Numeric date formats are preferred, though dates with an alphabetical month abbreviation are also acceptable.
The consumption-window part is what catches supplement brands. A 30-day supply needs its usage window plus 90 days. A 240-count bottle needs roughly eight months plus 90 days. The larger the count, the earlier that inventory has to reach Amazon, which changes your production calendar, not just your prep process.
[VERIFY: the minimum font size on the master carton, the required date format string, the single-expiration-date-per-box rule and the disposal window before expiry. Secondary sources publish 36-point font, MM-DD-YYYY or MM-YYYY, one expiration date per box, and a 50-day disposal cutoff, and they do not fully agree with each other on the minimum shelf life at receipt. Confirm all four against Seller Central.]
Carton rules
Once units are prepped, the carton has its own set of limits, and Amazon enforces these harder than most sellers expect. Amazon staff have quoted the policy directly on the seller forums: boxes must not exceed the standard weight limit of 50 lb unless they contain a single oversize unit that exceeds 50 lb, Team Lift labels are required for boxes over 50 lb and Mechanical Lift labels for single-unit boxes over 100 lb, and box weight and dimension policies are strictly enforced, with overweight or oversize boxes potentially leading to blocking of future shipments. On placement, a label clearly indicating Team Lift goes on the top and sides of the box. Jewelry and watch cartons carry a lower ceiling: boxes containing jewelry or watches must not exceed 40.00 lb.
| Carton rule | Limit |
|---|---|
| Maximum weight, multiple units | 50 lb |
| Exception | A single unit that weighs more than 50 lb on its own |
| Over 50 lb | Team Lift label, top and sides |
| Over 100 lb, single unit | Mechanical Lift label |
| Jewelry and watches | 40 lb maximum |
| Maximum side, standard units | 25 inches |
Every carton also needs its own FBA box label matching the shipment plan you created, and the box contents have to be declared. Do not reuse a box that still carries an old shipment label or a supplier barcode, because that is the same competing-barcode problem as on the unit, just at carton scale.
[VERIFY: whether Amazon currently charges a manual processing fee for boxes without electronically submitted box content information, and at what rate.]
Pallets and freight into Amazon
Once you are past roughly ten cartons, small parcel stops making sense and you move to less-than-truckload freight, usually shortened to LTL, where your pallets share a trailer with other shippers’ freight.
A compliant Amazon pallet is a specific build. The load sits square with no overhang, the cartons interlock rather than stacking in columns, the wrap is clear so labels stay readable, and the labels sit high enough on each face to scan without unwrapping anything.
[VERIFY: the published pallet specification. Secondary sources consistently list a 48 by 40 inch GMA wood pallet, four-way entry, a maximum loaded height of 72 inches including the pallet, a maximum loaded weight of 1,500 lb, clear stretch wrap only, and four pallet labels, one per side. We could not confirm any of these figures against an Amazon-owned page in this session, because the “Seller requirements for LTL, FTL and FCL deliveries” help page is behind a crawl block. Confirm each figure in Seller Central.]
Our part ends at the dock. We build, wrap and label the pallets to the spec on your shipment plan, and the freight itself moves on whichever carrier your plan specifies. Booking that freight and choosing the carrier stays with you.
Where the geography helps is on the back half of that trip. Our Jurupa Valley and Perris floors sit in the Inland Empire, within short drayage of the Amazon fulfillment centers most SoCal sellers route into, including ONT2, ONT8 and LAX9. A pallet that only has to travel across a county rather than across the country spends less time exposed to the handling that breaks wrap and tears labels.
The one-page brief to send your supplier
Most prep failures are upstream failures. If your factory can get this right at origin, you save the cost of doing it twice. Send them this, in writing, with photos of an approved sample:
- One FNSKU per variation, supplied by us, printed at 300 dpi on a thermal label.
- Label on a flat exterior surface, never on a seam, a fold or bubble wrap.
- Any existing barcode covered with an opaque label or blacked out completely.
- Bags transparent, minimum 1.5 mil, fully sealed, no more than 3 inches of excess.
- Suffocation warning pre-printed on any bag with an opening of 5 inches or more.
- Bundles banded or wrapped as one unit, interior barcodes covered, set label applied.
- Cartons under 50 lb and under 25 inches on any side unless a single unit exceeds it.
- Photograph one finished unit and one packed carton per SKU and send them before the container loads.
That last line is the one that earns its keep. A photo review costs you ten minutes. A container of mislabeled units costs you a rework quote and three weeks of sell-through.
When paying a 3PL to prep is the wrong call
We would rather tell you this now than after you have signed something.
If your product ships in sealed retail packaging with a printed barcode, you are brand registered, and you send a few hundred units a month, prep is not a hard job. A thermal label printer, a stack of pre-printed bags and an afternoon will cover it. Paying a per-unit prep fee on top of your landed cost for work that takes one person two hours is money you do not need to spend, and we will say so on the call.
If your supplier already preps to Amazon spec reliably and you have the photos to prove it, keep them. Prep at origin is almost always cheaper than prep in California, because you are not paying to move an unprepped unit across an ocean and then touch it again. Our honest advice is to audit a supplier who is close to compliant rather than replace them with us.
Where outsourcing does pay is when the math changes shape. High SKU counts with different prep flags per ASIN. Bundles that have to be assembled rather than just labeled. Inbound containers that arrive early and need somewhere to sit. Seasonal volume that would mean hiring temps you cannot keep busy in February. Or a supplier who has already failed a photo review twice.
And there are products we simply will not take. Cold-chain items and hazmat are outside what our buildings are set up for. If that is your category, a specialist is a better answer than us, and you should not have to find that out three weeks into onboarding.
How we handle prep
We have been prepping for Amazon since 2016, from four Southern California warehouses totaling more than 100,000 square feet. Units are labeled, bagged, bundled and cartonized against your shipment plan, and the plan is cross-checked before cartons close rather than after.
Our receiving and inbound process is where prep actually starts. Units are counted and inspected against the packing list on arrival, which is when a bagging or barcode problem gets caught while it is still cheap to fix. Orders across the rest of your catalog run at 99%+ order accuracy with same-day processing on anything placed before 2pm Pacific, and your Amazon FBA integration connects by direct API rather than a spreadsheet upload.
Pricing is per unit and per touch, stated before you sign, with a $500 monthly invoice minimum. If you want the full picture of what shows up on a fulfillment invoice, we broke down the fees that tend to surprise people in a separate post. Most clients are running live within 5 to 7 business days.
Tell us your SKU count, your monthly unit volume and which prep flags your listings carry. Custom proposal within 24 hours, no commitments and no hidden fees.