Amazon & marketplaces
Why Amazon rejects labels - and how to check a ZPL label before printing
An FBA shipment that arrives with bad labels is not simply refused; Amazon relabels the units at your cost, marks the shipment as a problem and, on repeat, r…
An FBA shipment that arrives with bad labels is not simply refused; Amazon relabels the units at your cost, marks the shipment as a problem and, on repeat, restricts your ability to send inventory. Almost every rejection traces back to one of eight causes, and all of them can be caught before the first label is printed.
The eight causes
| # | Cause | What the dock sees | Fix |
|---|---|---|---|
| 1 | Wrong barcode symbology | FNSKU printed as EAN/UPC, QR or Code 39 | FNSKU and box ID must be Code 128 (GS1-128 for SSCC) |
| 2 | No quiet zone | text, border or edge of the label touches the bars | ≥ 0.25 in free left and right; no frame around the barcode |
| 3 | Poor print quality | grey bars, gaps, smears | darkness 12-20, new ribbon/print head, matte stock, 203 dpi minimum |
| 4 | Wrong size | FNSKU smaller than 1 × 1 in, box label smaller than 4 × 6 in | use the template sizes; check ^PW / ^LL |
| 5 | Wrong or duplicate box ID | two cartons with the same label, box count does not match the plan | one label per carton, generated from the shipment plan |
| 6 | Label placed badly | over a seam, on the top, over an expiration date, on a curved surface | flat side of the carton, all edges taped |
| 7 | FNSKU covers nothing / covers wrong code | manufacturer barcode still visible next to the FNSKU | place the FNSKU over the manufacturer barcode |
| 8 | Missing human-readable text | barcode without the FNSKU or box ID printed under it | ^BCN,…,Y prints the interpretation line |
Checking ZPL automatically
The zplCloud ZPL linter has an Amazon FBA profile that runs these checks on any ZPL - your own template or the file Seller Central generated:
- FNSKU pattern
X0+ 8 alphanumerics in a Code 128 field - barcode symbology is
^BC(Code 128) or GS1-128 with FNC1 - interpretation line enabled
- module width at least 2 dots and the barcode inside the label width with quiet zones
- label size 1 × 2 in (unit) or 4 × 6 in (box / pallet) from
^PWand^LL - print darkness in a sane range and
^CI28for non-ASCII text
Open the ZPL linter, paste the label, choose the profile Amazon FBA and fix every warning before you batch-print. The same profile runs inside the designer's ZPL tab.
A scanner test costs one label
Print one label, scan it with a phone barcode app (or your warehouse scanner) and compare the decoded string with the FNSKU or box ID in the shipment plan. If a phone camera cannot decode it at 20 cm, a dock scanner will not either.
What it costs to get it wrong
Amazon publishes a per-unit fee for units it relabels in the fulfillment center and offers its own FBA Label Service at a per-unit price. Printing compliant labels yourself from a CSV costs the label stock - which is why an automated check before the print run pays for itself with the first shipment.
Overview: Amazon FBA labels · Guides: FNSKU label, FBA box label · Solution page: Amazon Seller