UPC Barcodes for Amazon: A Complete Guide for Taiwan Sellers

Amazon uses barcodes to match your physical product to your listing in their system. Without a valid UPC (or EAN for products primarily sold outside the US), Amazon cannot create your listing.

In 2016, Amazon tightened its barcode policy to require GS1-issued barcodes only — purchased directly from GS1, not from resellers. This was after widespread abuse where sellers bought recycled barcodes from unauthorized resellers, causing listing errors and catalog integrity issues.

If you try to list with a resold barcode, Amazon will send you a "barcode does not match GS1 database" error, and your listing will be suppressed. There is no workaround — you must buy from GS1 directly.

GS1 Taiwan: Taiwan has its own GS1 member organization at gs1tw.org. You can register for a Company Prefix (GS1 Company Prefix gives you a unique set of barcodes tied to your company) through GS1 Taiwan. Annual membership fee: approximately NT$5,000–10,000/year depending on your company size, which includes 100+ barcode numbers.

GS1 US: Alternatively, register directly with GS1 US at gs1us.org. This is preferable if your primary market is the US, as US retailers and Amazon US recognize GS1 US prefixes without question. Cost: $250/year for up to 10 unique product codes, $750/year for up to 100 codes.

Process: Register on the GS1 website, pay the annual fee, and you immediately receive your Company Prefix. Generate individual barcodes (GTINs) from your prefix using the GS1 portal. Download barcode images in EPS or PNG format for your packaging designer.

Important: each unique product variant (size, color, flavor) needs its own GTIN. A product in 3 sizes needs 3 separate barcodes.

UPC (Universal Product Code): 12-digit number, standard in the US and Canada. This is what you buy from GS1 US. Your physical product packaging has this barcode.

EAN (European Article Number): 13-digit number, standard in Europe, Japan, Taiwan, and most other countries. GS1 Taiwan issues EAN barcodes. Amazon accepts both UPC and EAN for listings.

ASIN (Amazon Standard Identification Number): Amazon's internal product identifier. Every listing on Amazon has a unique ASIN (e.g., B08XYZ1234). This is assigned by Amazon, not by you.

FNSKU (Fulfillment Network Stock Keeping Unit): Amazon's internal warehouse tracking code. This is what Amazon requires on each physical unit in their FBA warehouse — printed as a label placed on or over the manufacturer barcode. When you create an FBA shipment, Amazon generates FNSKU labels for you to apply. You can pay Amazon to label items ($0.55/unit) or label them yourself before shipping.

Option A — Apply UPC/EAN barcode on product packaging: Your Taiwan factory prints the GS1 barcode directly on the retail packaging. When Amazon receives your product, they scan the UPC to identify your listing. You must ensure the UPC is clean, scannable, and not obscured.

Option B — Apply FNSKU label: You or your freight forwarder applies an Amazon-generated FNSKU label over the UPC barcode on each unit before shipping to the warehouse. This is required if multiple sellers have the same product (commingled inventory) — FNSKU labels ensure Amazon routes the right seller's inventory.

If you enrolled in Brand Registry and use Stickerless Commingled Inventory (not recommended for most new sellers), your UPC alone is sufficient. Otherwise, FNSKU labels on each unit are the safe default.

Cost of labeling at the factory: build this into your supplier quote. Applying labels at a Taiwan factory before shipment typically costs $0.03–0.08/unit. Much cheaper than having Amazon label at $0.55/unit.