How to prep products for Amazon FBA: a step-by-step guide for UK sellers
Knowing how to prep products for Amazon FBA is the difference between stock that goes live quickly and stock that sits in a fulfillment centre waiting to be relabelled, repackaged or returned. This guide walks UK sellers through each stage in order: checking the listing, inspecting goods, FNSKU labelling, protective packaging by product type, cartons and pallets, creating the shipment and avoiding the most common errors.
MuggleShip · Updated · 10 min read
Key takeaways
- Decide on the barcode type and check the listing before any stock is labelled, because a wrong FNSKU is the costliest mistake to undo.
- Inspect every unit and remove or cover old barcodes so only one scannable barcode is visible on each sellable item.
- Match protective packaging to the product: fragile, liquid, sharp, textile, set and expiry-dated items each need different handling.
- Amazon sets the exact carton, pallet, bag and label requirements, so check the current rules in Seller Central before every shipment.
- Outsourcing to a prep centre makes sense once prep time, error rates or volumes start to outgrow your own space and staff.
Step 1: Check the listing, barcode type and supplier packaging
The first step in how to prep products for Amazon FBA happens on screen, not in the warehouse. Open each ASIN in Seller Central and confirm the title, variation, pack quantity and images match what your supplier is actually sending. A listing for a single mug cannot receive a box of mugs packed in pairs, and a mismatch found at the fulfillment centre is far harder to fix than one found at your desk.
Next, confirm the barcode type for each SKU. Most private-label sellers use an FNSKU (Fulfillment Network Stock Keeping Unit), the Amazon-generated barcode that ties a unit to your seller account, rather than the manufacturer barcode. With manufacturer barcodes, identical units from different sellers can be treated as interchangeable, which is why many brands prefer FNSKU labels for traceability.
Finally, ask your supplier exactly how goods will arrive: retail boxes or loose units, shrink-wrapped or open, how many per master carton, and which barcodes are printed on the packaging. That answer tells you how much prep work is coming before the pallet lands.
Step 2: Inspect stock before you label anything
Inspection is easiest when the stock first arrives, before cartons are broken down and mixed. Count units against the supplier's packing list and the purchase order, then open a sample of cartons from different parts of the consignment rather than just the top layer. If the sample turns up problems, check every unit of that SKU.
- Quantity — confirm the count per carton and in total matches what you ordered and what you plan to send to Amazon.
- Condition — look for crushed corners, torn retail packaging, broken seals, leaks, scratches and missing parts or accessories.
- Correct product — check colour, size and variant against the listing, especially for parent/child variations that look similar in the carton.
- Existing barcodes — note which units carry scannable UPC or EAN codes, supplier stickers or old FNSKU labels that will need removing or covering.
- Dates and batches — record expiry dates and batch codes for consumables, cosmetics and supplements before they disappear inside outer packaging.
Set aside anything damaged or wrong and raise it with the supplier straight away. Units that customers would return as "not as described" cost you more once they are in Amazon's network than they do on your bench. Photograph any damage with the carton label visible, so you have evidence for a supplier claim.
Step 3: Remove old labels and apply FNSKU labels
Every unit should present exactly one scannable barcode to Amazon's receiving team: the one linked to your listing. Peel off supplier stickers, price tags and old FNSKU labels from previous shipments. Where a manufacturer barcode is printed on the packaging and you are using FNSKU labels, place the FNSKU label so it fully covers the printed barcode, or cover the old code with a blank opaque label.
Print FNSKU labels from Seller Central using the label format and paper that Amazon currently specifies, on a printer that produces sharp, unsmudged bars. Many sellers use a thermal label printer because the labels stay readable and peel cleanly. Apply each label to a flat, smooth surface where it will not wrap around a corner or curve, and keep it clear of seams and openings.
Before labelling a full batch, scan a few test labels with a phone barcode app or handheld scanner and confirm they read as the correct FNSKU. Mislabelled units are counted against the wrong ASIN, and correcting that later is slow.
Step 4: Choose protective packaging by product type
Amazon's prep and packaging requirements differ by product category, and the details change from time to time, so check the current guidance in Seller Central for each SKU. The principles below explain why each type of product needs extra care and what that usually looks like in practice.
- Fragile items — a glass candle or ceramic plate should be bubble wrapped so it survives a drop, then boxed so nothing rattles when shaken.
- Liquids — seal caps with tape or a secondary closure, then poly bag the bottle so any leak cannot damage neighbouring stock.
- Sharp items — knives, scissors and tools with exposed points or edges need covering so they cannot cut through packaging or injure handlers.
- Textiles and soft goods — poly bagging for FBA keeps tea towels, clothing and cushions clean and dust-free on shelves and in transit.
- Sets and bundles — a set of three tea towels sold as one SKU must be bagged or banded together and marked so it is not split.
- Expiry-dated goods — food, supplements and cosmetics need the expiry date clearly visible on each unit and on the outer carton.
- Small items — loose parts and accessories are easily lost or mis-scanned, so bag them and label the bag rather than the item.
Poly bags often need a suffocation warning and must be transparent enough for the barcode to be scanned, or carry the FNSKU label on the outside. Amazon sets minimum bag thickness and warning rules, so confirm the current specification before you buy packaging in bulk.
Step 5: Pack cartons and palletise larger consignments
Prepping stock for Amazon fulfillment centres does not end at the unit. Use strong, double-walled cartons in good condition, fill empty space with paper or air pillows so contents cannot shift, and avoid reusing supplier boxes that still carry old shipping labels or barcodes. Amazon sets maximum carton weights and dimensions, and heavier cartons need team-lift or mechanical-lift markings, so check the current limits in Seller Central's packaging requirements before you pack.
Each carton needs the shipping label that Seller Central generates for that specific box. Place it on a flat side, away from seams, and remove or cross out any older labels so the carrier and the fulfillment centre only see one. Keep a simple record of which units went into which carton; you will need it when entering box contents.
For larger consignments, cartons are usually palletised. Stack the heaviest boxes at the bottom, keep the load square and within the pallet edges, stretch-wrap it firmly and attach pallet labels to the sides as instructed. Amazon specifies pallet type, height and weight limits, so confirm them before you book collection.
Step 6: Create the shipment in Seller Central
With stock inspected, labelled and packed, you can build the inbound shipment. Have your carton measurements and packing record to hand before you start. Seller Central's shipment workflow guides you through each stage, but the order below helps you avoid going back and forth between the screen and the packing bench.
- Select the SKUs and quantities you are sending and confirm the prep and labelling owner for each, whether that is you or Amazon.
- Enter the case-pack or individual-unit details and box contents accurately, because receiving staff check incoming cartons against this information.
- Enter carton weights and dimensions from real measurements taken with scales and a tape, not from the supplier's specification sheet.
- Review the destination fulfillment centres Amazon assigns; your shipment may be split across several sites, each needing its own cartons and labels.
- Choose the carrier option, print the carton and pallet labels for each shipment, and apply them to the matching boxes.
- Book collection or drop-off, then record the tracking details in Seller Central so the shipment can be followed through to receiving.
Once the shipment is marked as received, compare the received quantities with what you sent. Any shortfall is easier to investigate while your packing records and carton photographs are still fresh, and Seller Central sets time windows for raising receiving discrepancies, so check them and act promptly.
Common mistakes that get FBA stock held, rejected or unfulfillable
Most problems at receiving trace back to a small number of avoidable errors. Each one can delay your stock going live, lead to prep or labelling charges, or leave units classed as unfulfillable and waiting for you to arrange a return or disposal.
- Two scannable barcodes on one unit, such as an exposed manufacturer EAN beside the FNSKU, so the scanner cannot tell which product it is.
- FNSKU labels printed for the wrong variant, so a large red jumper is received against the listing for a small blue one.
- Sets and multipacks not secured or marked as sets, which allows them to be split and sold as single units.
- Liquids without sealed caps or bags, which leak in transit and can make whole cartons of other stock unsellable.
- Expiry dates missing, hidden or too close for Amazon's acceptance rules for that category.
- Box contents entered incorrectly, or cartons sent to the wrong fulfillment centre after a split shipment.
- Overweight or oversized cartons, and unstable pallets that shift or collapse before they reach the receiving dock.
A short final checklist taped to the packing bench, covering barcodes, sets, sealing, dates and carton labels, catches most of these issues before the courier arrives. Ask a second person to run through it on the first carton of every SKU, when a fresh pair of eyes is most useful.
When it makes sense to use an FBA prep centre
Doing your own FBA prep is sensible when you send a handful of SKUs a few times a year and have the space to work. It becomes harder to justify when labelling and bagging take up whole days, when stock arrives from overseas suppliers and has to be broken down somewhere first, or when receiving errors keep costing you time and stock.
A prep centre receives your stock, inspects it, labels and packages it to Amazon's requirements and sends it on to the fulfillment centres. MuggleShip's FBA Prep service does this from our Bedford warehouse: quality inspection of every item, removal of old labels and barcodes, FNSKU labelling, poly bagging and bubble wrap, palletisation to Amazon's requirements and shipping directly into Amazon FBA fulfillment centres on your behalf.
Pricing is quote-based, with no setup fees or monthly subscriptions, and you pay only for the prep work you use. If you want to compare it with the time your team spends on prep now, send us your SKU count and typical shipment sizes for an itemised quote.
Frequently asked questions
How do I prep products for Amazon FBA as a UK seller?
Confirm the listing and barcode type in Seller Central, inspect the stock, remove old barcodes and apply FNSKU labels, add protective packaging suited to each product, pack and label cartons, palletise larger loads and create the shipment in Seller Central. Check Amazon's current prep and packaging requirements for your categories before each shipment, as the details can change.
Do I need FNSKU labels or can I use the manufacturer barcode?
Some products can be sent using the manufacturer barcode, but units from different sellers may then be treated as interchangeable. FNSKU labels link each unit to your account, which keeps your stock traceable. Your choice is set per SKU in Seller Central, and Amazon's eligibility rules for manufacturer barcodes are listed there.
Which products need poly bagging for FBA?
Poly bagging is commonly needed for textiles, soft goods, liquids, small loose items and products sold as sets, because a bag keeps them clean, contained and together. Amazon's category rules decide exactly which products must be bagged and what warnings and bag specifications apply, so check the current prep requirements in Seller Central for each SKU.
What are Amazon's FBA carton weight and size limits in the UK?
Amazon sets maximum carton weights and dimensions, plus extra labelling for heavy cartons, and these can be updated. Rather than relying on figures from older articles, check the current shipping and packaging requirements in Seller Central before you pack, and measure and weigh every carton rather than using supplier estimates.
Can a UK prep centre send my stock straight into Amazon?
Yes. MuggleShip's FBA Prep service receives stock at our Bedford warehouse, inspects every item, removes old labels, applies FNSKU labels, adds poly bagging or bubble wrap, palletises to Amazon's requirements and ships directly into Amazon FBA fulfillment centres on your behalf. We provide an itemised, no-obligation quote within 24 hours of an enquiry.