How to Implement GTINs: A Beginner's Guide

Adding GTINs to your products may sound technical, but for most businesses it follows a clear, manageable set of steps. This beginner-friendly guide walks through how to implement GTINs so your products can be accurately listed, tracked, and sold across retail, e-commerce, and logistics channels.

Step 1: Confirm which products need GTINs

Not every internal item requires a GTIN, but most consumer retail products do. Use GTINs for standalone sellable items and distinct variants (size, color, flavor, pack count). Bundles or multipacks often need their own GTIN if sold as a fixed unit.

Step 2: Join GS1 and obtain a company prefix

GS1 is the global body that issues company prefixes used to create GTINs. Contact the GS1 organization in your country, register your business, and obtain a prefix. The prefix length affects how many unique GTINs you can create — shorter prefixes allow more item references.

Step 3: Assign GTINs to each trade item

Using your GS1 prefix, build GTIN numbers by combining the prefix, an item reference you choose, and the standard check digit. Ensure each distinct trade item gets one unique GTIN and do not reuse GTINs for different products.

Step 4: Determine barcode format and print placement

Choose the right barcode symbology for each GTIN and packaging type. Common mappings:

• GTIN-12 (UPC-A) — typical for North American retail.
• GTIN-13 (EAN-13) — typical for international retail outside North America.
• GTIN-14 (ITF-14) — used for cartons, cases, or pallet labels.

Design considerations include barcode size, quiet zones (margins), contrast between bars and background, and avoiding placement over seams, edges, or curved surfaces where scanning is harder.

Step 5: Add product data where needed

GTINs are more powerful when paired with accurate product details in systems and marketplaces. Maintain tidy records for each GTIN including product name, brand, description, dimensions, weight, images, and any attribute required by retailers or marketplaces. Use a central master data file or a PIM (Product Information Management) system if you have many SKUs.

Step 6: Register GTINs with trading partners and marketplaces

Major retailers and online marketplaces often request GTINs during onboarding. Submit your GTIN and product data to their vendor portals or data feeds. For marketplaces like Google Merchant Center or Amazon, correct GTINs improve discoverability and are sometimes required for product listing approval.

Step 7: Test and validate barcodes

Before large-scale printing, test samples with handheld scanners and mobile devices. GS1 provides verification services that validate barcode size, encoding, and print quality. Fix barcode contrast or sizing issues early to avoid scanning failures in stores or warehouses.

Step 8: Track and maintain GTIN records

Assign internal ownership for GTIN management. Keep a record of issued GTINs, their corresponding SKUs, packaging versions, and launch dates. If a product changes in a way that affects its trade item identity (for example, a new formulation or a different net weight), issue a new GTIN rather than reusing the old one.

Practical examples and tips

• If you sell the same product in 250 g and 500 g sizes, each size needs its own GTIN. If you sell the same 500 g bag in different flavors, each flavor needs a unique GTIN.
• When creating multipacks (for example, a 6-pack of the same bottle), decide whether the multipack is a separate trade item. If sold as its own SKU, it should have its own GTIN and barcode on the multipack packaging.
• Avoid buying GTINs from third-party resellers without GS1 provenance. Some marketplaces verify the GS1 company prefix and may flag non-GS1 numbers.

Costs and timeline

Costs vary by country and the size of the prefix you choose. There is usually an initial GS1 registration fee and an annual renewal fee. The time to implement ranges from a few days for a handful of products to several weeks for larger catalogs where artwork, barcode testing, and marketplace onboarding are required.

In short, implementing GTINs is a step-by-step process: identify which items need GTINs, join GS1, assign and record each GTIN, print and test barcodes, and use the GTINs consistently across your sales and logistics channels. Following these steps will reduce errors, speed onboarding to retailers and marketplaces, and make your supply chain and sales data far more reliable.