5 Critical FBA Prep Mistakes That Will Get Your 2026 Shipments Rejected
As of January 1, 2026, Amazon no longer handles prep or labeling on your behalf. Every unit must be fully compliant before it touches the fulfillment center conveyor belt — and inbound defect fees now reach up to $5.72 per unit for standard items and $8.25 for oversize.
Repeated violations can result in blocked shipments and account health degradation. Here are the five most common FBA prep mistakes causing rejections — and exactly how to eliminate each one.
Mistake 1: Unmasked Manufacturer Barcodes
Every FBA unit must display one scannable barcode only. Visible manufacturer barcodes (UPC, EAN, ISBN) alongside FNSKU labels trigger unscannable flags. After March 31, 2026, resellers must use FNSKU labels exclusively — no manufacturer barcodes allowed.
The fix: Apply FNSKU labels over every existing barcode with complete coverage. Verify with a handheld scanner before sealing.
Mistake 2: Missing Safety Labels on Heavy Cartons
Cartons weighing 33 lb (15 kg) to 50 lb require "Team Lift" safety labels on all five sides. This applies even when under the 50 lb maximum weight limit.
The fix: Weigh every carton, apply Team Lift labels to all five sides of 33+ lb boxes, use local language labels for destination country.
Mistake 3: Poly Bag Thickness Violations and Missing Suffocation Warnings
Poly bags must be 1.5 mil minimum thickness, transparent, sealed with adhesive strips. Bags with 5"+ openings require 24-point suffocation warnings visible after sealing.
The fix: Source pre-printed 1.5 mil bags with warnings. Inspect samples from every batch and confirm visibility after sealing.
Mistake 4: Non-Scannable Labels on Curved Surfaces
Labels on curves, seams, folds, or glossy stock fail automated scanners. Low-resolution printing also triggers rejections.
The fix: Place FNSKU on flat smooth surfaces only. Use white matte labels, 300+ DPI thermal printing. Test scannability through outer packaging.
Mistake 5: Exceeding Box Dimension and Weight Limits
Maximum 50 lb weight, 25" dimensions per box. No taped-together boxes, damaged cartons, or banned dunnage (peanuts, shredded paper).
The fix: Weigh/measure every carton. Use new corrugated boxes. Approved dunnage only: bubble wrap, air pillows, polyethylene foam.
Pre-Ship Checklist
- One scannable barcode per unit — manufacturer barcodes fully covered
- FNSKU on flat surface, scannable through packaging, 300+ DPI
- Poly bags 1.5 mil minimum, adhesive sealed, suffocation warning visible
- Team Lift labels on 33+ lb cartons (all five sides)
- No box exceeds 50 lb or 25" dimensions
- New corrugated boxes, approved dunnage only
- "Sold as Set" stickers on bundles
- Final scan test on sample cartons
The Cost of Getting It Wrong
Inbound defect fees charge automatically: $0.32–$5.72 standard, $0.85–$8.25 oversize. Rejected inventory kills in-stock rates and Buy Box eligibility. These five mistakes cause most inbound failures — eliminate them to clear receiving cleanly.