Chapter 26: Prep and labelling
What you'll learn: how to label every unit with an FNSKU, the packing rules you'll use most often, UK box limits, and a simple starter kit so your first shipment arrives ready to sell.
Prep is your responsibility, or a prep centre's if you pay one. The rules below are the ones UK sellers use every day: an FNSKU on each unit, the right bagging where needed, and boxes within Amazon's UK weight and size limits.
Label every unit
Amazon identifies your stock by an FNSKU barcode on each unit. Without it, the unit can't be received against your account.
- Print the labels from Seller Central when you create your shipment (Chapter 27), or from the product's inventory page. Each label shows a scannable barcode, the FNSKU code, a short product title and the condition (for example, "New").
- Apply one label to every unit, on a flat part of the packaging. Don't put it on a corner or a curve.
- Cover the manufacturer's barcode (the EAN or UPC) so Amazon's scanners read your FNSKU, not the original code. Opaque tape or a label that fully covers it both work. Leave any Transparency code or serial number barcode uncovered (Chapter 23).
- Keep the barcode scannable after any polybagging or bubble wrap: either place the FNSKU on the outside, or make sure it can be read through a clear bag.
An FNSKU label: Code 128 barcode, FNSKU, short product title and condition (New), on a plain box. Simplified illustration – the real screen may look different.
"Prep and labelling (UK)": printing FNSKUs, covering the manufacturer barcode, polybagging a unit and packing a box to the UK weight and size limits.
Pack the unit
Polybags. Bag a unit when it needs protection, when the packaging could open in the fulfilment centre, or when the prep guidance for that ASIN asks for a bag.
- At least 1.5 mil (0.0254 mm) thick, and fully sealed.
- The bag should fit well and not hang more than 7.5 cm past the product. Tape down loose edges if needed.
- The FNSKU must be scannable on or through the bag.
- If the opening is more than 12 cm, add a suffocation warning, for example: "Warning: To avoid danger of suffocation, keep this plastic bag away from babies and children."
- Highly scented products (such as candles) should be sealed or bagged so the scent doesn't affect other stock.
Bubble wrap. Use it for glass, ceramic and other fragile items so the product can't move inside the wrap. Seal it with tape, and put the FNSKU on the outside.
Sold as a set. If several items sell together under one ASIN, seal them so they can't be separated and add a clear label such as "Sold as set" or "Do not separate". Cover or hide barcodes on the individual items inside so only the set's barcode is scanned.
Expiry-dated products. Follow the date formats and shelf-life rules in Chapter 24. Put the date on each unit, and on the outer pack of a multipack, and keep one expiry date per ASIN in each box.
Read Amazon's full guide: Product packaging requirements.
Pack the box (UK limits)
Amazon enforces these UK box limits on every inbound parcel:
| Rule | Limit |
|---|---|
| Maximum weight | 23 kg (a single oversize item may go up to 30 kg; heavier needs Heavy & Bulky) |
| Maximum side | 63.5 cm (unless the box holds one oversize item longer than that) |
| Minimum size | 15.2 × 10.0 × 2.5 cm |
| Minimum weight | 0.15 kg |
| Over 15 kg | Add "Team Lift" / "Heavy Parcel" labels on the top and sides (5 labels in total) |
Also:
- Use a rigid, six-sided cardboard box with the flaps intact. Don't bag boxes, wrap them in stretch film, strap them together or cover them in tape.
- One shipment ID per box: don't mix products from different shipments in the same box.
- Remove or cover any scannable barcodes on the outside of the shipping box, other than the Amazon box label you'll add in Chapter 27.
- Give Amazon accurate box weights and dimensions when you create the shipment.
Source: Shipping and routing requirements.
Sealing a packed box with tape. Photo: RDNE Stock project / Pexels.
What to have on hand
A small home set-up is enough to begin:
- A thermal label printer and labels sized for FNSKUs and box labels (common sizes are 100 × 150 mm for box labels and smaller for product labels)
- Clear polybags of a few sizes, with suffocation-warning stickers
- Bubble wrap, strong packing tape and a tape gun
- A set of scales that can weigh more than 23 kg, and a tape measure
- Sturdy cardboard boxes within the size limits above
- A marker pen for covering stray barcodes on outer boxes
As you grow, a prep centre can label, bag and box for you for a per-unit fee. Many sellers start at home and move some or all of the work across later.
Checklist
- Every unit has an FNSKU label covering the manufacturer barcode
- Transparency codes (if any) are left uncovered
- Polybags are sealed, scannable and carry a suffocation warning when needed
- Sets are sealed and labelled "Sold as set"
- Each box is within 23 kg and 63.5 cm, with Team Lift labels if over 15 kg