Lumina

GTINGlobal Trade Item Number

A globally unique identifier issued by GS1 for a product or product variant — the umbrella standard that includes UPC and EAN.

By Oana Bradulet

A GTIN (Global Trade Item Number) is a globally unique identifier for a product or product variant, issued through the GS1 standards organisation. It's the umbrella term that includes UPC, EAN, and JAN — all of which are GTIN formats.

If your product has a barcode on the packaging, that barcode encodes a GTIN. Retailers, marketplaces, and customs systems use it as the universal product identifier. Two retailers in different countries scanning the same product see the same GTIN — that's what makes it useful.

For consumer brands, the GTIN is the external identifier that connects your product to the rest of the world. The SKU is internal; the GTIN is external. Every sellable variant should have one.

GTIN-8, GTIN-12, GTIN-13, GTIN-14

Four variants exist, distinguished by digit length:

  • GTIN-12 — 12 digits. The most common in North American retail. This is what most people call a UPC.
  • GTIN-13 — 13 digits. The European and global default. This is what most people call an EAN.
  • GTIN-14 — 14 digits. Used for case packs, master cartons, and shipping units. Identifies the outer container, not the consumer unit.
  • GTIN-8 — 8 digits. A short format for very small items where a full 13-digit barcode wouldn't fit. Less common.

GS1 and modern systems treat all four as variants of the same standard. The GTIN field accepts any length; checksum and country prefix logic adapts.

How a GTIN gets assigned

Three paths:

Apply through GS1. The official route. Your business gets a company prefix (typically 7–9 digits identifying your company), and you allocate item numbers within that prefix. One-time fee + annual fee scales with the number of GTINs you need.

Use a barcode reseller. Cheaper for small ranges. The reseller bought a GS1 prefix in bulk and resells individual GTINs. The GTIN is technically valid but registered to the reseller, not you. Major retailers (Amazon, Tesco) sometimes reject these — verify before committing.

Inherit from a manufacturer. If you sell another brand's products under wholesale, the GTIN is theirs, not yours. You don't need to create new ones.

For most own-brand consumer products, going direct to GS1 is the right call. The annual fee is small relative to the cost of having Amazon reject your listings because the GTIN isn't legitimately yours.

GTIN vs SKU vs UPC vs EAN

The most commonly confused identifiers in retail. Distinct definitions:

  • SKU — your internal identifier. You invent it. Format is your choice. Only meaningful inside your business.
  • GTIN — global external identifier issued through GS1. Standardised. Recognised worldwide.
  • UPC — a specific format of GTIN: the 12-digit form used in North American retail.
  • EAN — a specific format of GTIN: the 13-digit form used in Europe and most other markets.

A single SKU usually maps to one GTIN. The GTIN may exist as both a UPC (if you sell in the US) and an EAN (if you sell in Europe), but they're different numbers identifying the same product in different barcode encodings.

When you need a GTIN

Three triggers:

  1. Selling on a major marketplace. Amazon, eBay, Google Shopping, Tesco, Argos — almost all require a valid GTIN for product listings. Counterfeits and grey-market sellers can sometimes use placeholders, but legitimate brands need real GTINs.

  2. Selling through wholesale or retail channels. Buyers want a GTIN they can scan and resell under their POS systems.

  3. Operating internationally. Customs, freight forwarding, and cross-border logistics use GTINs as universal identifiers. Easier than managing different SKU codes per market.

If you're DTC-only on your own site, you can technically operate without GTINs. But the moment you expand into marketplaces or wholesale, you'll need them — better to allocate from day one.

Common GTIN mistakes

  • Reusing a GTIN across product variants. Each unique sellable variant needs its own. A black t-shirt in size S has a different GTIN from the same shirt in size M.
  • Buying cheap GTINs from resellers when you'll need legitimate ones. Saves £100 today, blocks a £100k Amazon launch tomorrow.
  • Treating GTIN and SKU as the same field. They're different things doing different jobs. Map them; don't merge them.
  • Forgetting to register new variants. Every new SKU = a new GTIN. Skipping this for one launch creates a gap that compounds.

Common mistakes

  • →Reusing a GTIN across product variants — each sellable variant needs its own.
  • →Buying cheap GTINs from resellers when you'll later need legitimate GS1-registered ones for major marketplaces.
  • →Confusing GTIN with SKU — they're different identifiers doing different jobs.
  • →Forgetting to allocate a new GTIN for every new product variant.

How Lumina handles GTINs for scaling brands

Lumina maps every SKU to its GTIN and the channel-specific identifiers (Amazon ASIN, retailer codes) so a single product variant flows cleanly from your forecast to your suppliers, retailers, and marketplaces — no reconciliation between four different ID systems.

Frequently asked questions

What does GTIN stand for?
GTIN stands for Global Trade Item Number — a globally unique product identifier issued through the GS1 standards organisation. It's the umbrella standard that includes UPC, EAN, and JAN.
What is the difference between a GTIN and a UPC?
GTIN is the umbrella term; UPC is one specific format. A UPC is a 12-digit GTIN used in North American retail. An EAN is a 13-digit GTIN used in Europe. Both are valid GTINs in different lengths.
How do I get a GTIN for my product?
Apply through GS1 in your country (e.g. GS1 UK). You'll receive a company prefix and can allocate item numbers within that prefix. There's an annual fee that scales with the number of GTINs you need. Cheap third-party GTIN resellers exist but major marketplaces often reject them.
Do I need a GTIN to sell on Amazon?
Almost always yes. Amazon requires a valid GTIN (UPC or EAN) for most product categories. Some private-label sellers can apply for GTIN exemption, but this is increasingly hard to get. Plan to have legitimate GS1-registered GTINs.
What's the difference between GTIN and SKU?
GTIN is a global external identifier (standardised, recognised worldwide). SKU is your internal identifier (you invent it, only meaningful inside your business). One SKU usually maps to one GTIN, but they're separate fields with different roles.

Related terms

SKU— Stock Keeping Unit

A unique internal code your business uses to identify and track every distinct product variant.

UPC— Universal Product Code

A 12-digit barcode standard used for product identification, primarily in North American retail.

EAN— European Article Number

A 13-digit barcode standard used for product identification across Europe and most of the world outside North America.

Purchase order— Purchase Order (PO)

A formal document that a buyer issues to a supplier specifying what to ship, in what quantity, at what price, and when.