When Amazon requires an FNSKU instead of a manufacturer UPC
Amazon uses two barcode systems at inbound receiving: manufacturer barcodes (UPC-A or EAN-13) and Amazon-assigned FNSKU codes (starting with X00). Whenever a listing is private-label, bundled, expiration-dated, topical, or set to Amazon barcode in Seller Central, every unit must carry an X00 FNSKU sticker covering any existing UPC.
If a unit arrives with both the original UPC and the FNSKU exposed, receiving optical scanners can read the wrong symbol and trigger an unplanned prep fee of $0.35 to $1.50 per unit.
| Identifier | Format | Prefix | Who uses it |
|---|---|---|---|
| Amazon FNSKU | Code 128A | X00 (10 chars) | Private-label & non-commingled FBA inventory |
| Manufacturer UPC-A | GS1 UPC-A | 12 digits | Commingled stickerless retail brands |
| Manufacturer EAN-13 | GS1 EAN-13 | 13 digits | International & European retail inventory |
The four mandatory elements on an FNSKU sticker
Under Amazon Seller Central Item Label Specification G200141490, an FBA item sticker must remain clean of marketing text, URLs, or retail prices. Only four elements belong inside the die-cut boundary:
- Code 128A barcode symbol in pure black ink on non-reflective matte white paper.
- The 10-character alphanumeric FNSKU string (such as X001ABCDE9) centered directly beneath the bars.
- A concise product title so warehouse staff can visually identify the item.
- The raw item condition (for example, New or Used - Like New) without a 'Condition:' label prefix.
Approved label sizes & quiet-zone margins
Amazon accepts sticker dimensions between 1 × 2 in and 2 × 3 in, provided the barcode leaves at least 0.25 in (6.35 mm) of blank white space on the left and right sides and 0.125 in (3.18 mm) on the top and bottom.
| Paper stock | Sticker size | Layout | Printer type |
|---|---|---|---|
| Avery 5160 | 2.625 × 1 in (66.7 × 25.4 mm) | 30 per US Letter sheet | Laser printers |
| Avery 8160 | 2.625 × 1 in (66.7 × 25.4 mm) | 30 per US Letter sheet | Inkjet printers |
| Thermal Roll | 2 × 1 in (50.8 × 25.4 mm) | 1 per roll advance | Zebra, Rollo, Dymo |
Frequently asked questions
Can I print multiple different FNSKU products on one Avery 5160 sheet?
Yes. Seller Central exports one product per PDF page, which wastes partial sheets. In our Amazon FNSKU Barcode Maker you can add multiple FNSKU rows with exact quantities—for example, 10 of SKU A and 20 of SKU B—to fill all 30 stickers on a single sheet.
What happens if my printer scales the FNSKU PDF to 96%?
Fit-to-page scaling shrinks the 10 rows toward the center of the sheet, causing rows 8 through 10 to cross the die-cut perforation lines. Always set your PDF print dialog to 100% or Actual Size.