Overview
This page covers common expectations across major retail channels, explains when GS1-issued GTINs versus reseller-issued GTINs may face different scrutiny, and outlines the product data preparation steps that are often separate from barcode generation itself.
Getting your products into retail stores or onto online marketplaces requires more than just a valid barcode image. Retailers and marketplaces have specific expectations around GTIN uniqueness, symbol print quality, and—in some cases—provenance verification. Understanding these requirements before you list or ship can prevent costly rejections, listing takedowns, or relabelling.
The core requirement: unique GTIN per product variant
Retailers and marketplaces require a unique GTIN for every distinct product variant. This means:
| Variant change | GTIN requirement |
|---|---|
| Size (e.g., S, M, L) | Separate GTIN |
| Color | Separate GTIN |
| Flavor / scent | Separate GTIN |
| Pack quantity (single vs. 6-pack) | Separate GTIN |
| Material or ingredient change | Separate GTIN |
| Packaging redesign (no content change) | Usually same GTIN |
| New batch/lot, same product | Same GTIN (use lot codes to distinguish batches) |
This requirement exists because GTINs are the backbone of inventory management, point-of-sale systems, and supply chain tracking. Duplicate or reused GTINs create data collisions—two different products appearing as one in a retailer’s system.
For guidance on how many barcodes your product line needs, see How many barcodes do I need?
Marketplace-specific expectations
Amazon
Amazon enforces GTIN requirements strictly across most categories. Key policies include:
- GTIN exemption: For products that do not have a GTIN. Available only for specific categories (handmade, certain private-label goods without existing identifiers) and must be applied for in advance.
- Brand-gated categories: If you sell in categories where Amazon has brand registry requirements, your GTIN will be cross-checked against GS1’s GEPIR database or Amazon’s own records to verify that the GTIN prefix matches the brand owner submitting the product to be sold on Amazon.
- The ownership documents produced by Barcode resellers typically do not satisfy Amazon’s brand check, and thus reseller GTINs are discouraged from use on Amazon.
- Duplicate suppression: Listings with GTINs already assigned to other ASINs may be blocked or merged.
eBay
eBay’s requirements are generally less stringent. The platform encourages GTINs for better search visibility and catalog matching but does not universally mandate them. When provided, GTINs should be valid and unique to the specific item.
Google Shopping / Google Merchant Center
Google requires GTINs for all products where a GTIN exists (i.e., manufacturer-assigned identifiers are available). This applies broadly to branded goods. Products without GTINs receive lower priority in listings and may be disapproved for certain program features.
Google validates GTIN check digits but does not, as a matter of stated policy, verify ownership against GS1’s database.
Walmart Marketplace
Walmart requires GTINs for most products and performs catalog matching. Like Amazon, Walmart’s systems may flag inconsistencies between submitted product data and existing catalog entries tied to specific GTINs.
Other platforms (Etsy, Shopify, regional marketplaces)
Requirements vary significantly. Handmade or custom goods platforms often do not require GTINs at all. Integrated point-of-sale systems (e.g., Shopify POS) typically need valid, scannable barcodes but may not enforce uniqueness or provenance checks.
When GS1 ownership gets checked
Some marketplaces and retailers—particularly for high-risk or brand-sensitive categories—have begun checking whether the GTIN prefix (the company prefix embedded in the GTIN) matches the brand name on the product or in their records.
| Scenario | Typical outcome |
|---|---|
| GTIN from GS1, prefix matches your brand | Usually smooth acceptance |
| GTIN from GS1, prefix matches a different brand | Likely rejection or flagging |
| GTIN from reseller, no ownership check performed | Accepted if valid checksum digit and unique |
| GTIN from reseller, ownership check performed | May require additional ownership documentation from the seller, or rejection if retailer only accepts ownership checks from GS1 |
| GTIN from reseller, previously used by another company | High risk of rejection |
This ownership verification is not universal between retailers. It tends to concentrate in retailers dealing in:
- Health and beauty
- Electronics
- Nutritional supplements
- Baby products
- Categories with high counterfeit risk
For sellers using reseller-issued GTINs, the International Barcodes Network’s regional members can provide individualized guidance on checking barcode validity and understanding when additional scrutiny may apply at local retailers.
Product data submission: beyond the barcode image
A common misconception is that generating a barcode image completes the preparation process. In practice, retailers almost always require structured product data submission through separate systems:
| Retailer / channel | Data system | Typical requirements |
|---|---|---|
| Major grocery/retail chains | GDSN (Global Data Synchronization Network) or direct portal | Weight, dimensions, ingredients, images, case pack info |
| Amazon | Seller Central / Vendor Central | Title, bullets, images, browse nodes, shipping weight |
| Walmart | Supplier Portal / Item 360 | Similar to GDSN fields |
| Google Shopping | Merchant Center Feed | Title, description, price, availability, GTIN, MPN, brand |
| Smaller retailers | Spreadsheet, EDI, or direct entry | Varies widely |
The barcode image (EPS, PNG, PDF) is used for physical packaging. The product data feed is used for digital systems. These are separate deliverables.
Key data quality tips
- Consistency: Ensure your GTIN in the data feed exactly matches the printed barcode (no leading zeros added or dropped unless your system specifically requires them).
- Image standards: Most retailers require white backgrounds, minimum resolution, and specific angles.
- Weight and dimensions: Used for shipping calculations; inaccuracies can trigger chargebacks.
- Multipacks: Clearly distinguish “sell unit” GTIN from “case” or “inner pack” GTIN if applicable.
Retailer acceptance: what can and cannot be promised
No barcode reseller, consultant, or even GS1 itself can guarantee that every retailer or marketplace will accept a given GTIN. Acceptance depends on:
- The specific retailer’s policies (which change over time)
- The product category
- Whether ownership verification is performed
- Historical data conflicts (if a GTIN was previously used differently)
- Regional or country-specific regulations
What you can do to maximize acceptance:
- Use valid GTINs that were allocated for use and checked for uniqueness by an authority or a reputable reseller
- Ensure uniqueness—never reuse GTINs across different products
- Register your product data in a visible database where appropriate (Barcodes Database is one option)
- Prepare complete, accurate product data submissions
- For brand-sensitive categories, understand whether the target channel performs prefix ownership checks, and whether your proof of GTIN ownership will meet the channel’s requirements (GS1 database check, reseller ownership document)
- Ensure your physical barcode symbol is of high quality print so it scans well. Some retailers require verification that the barcode symbol meets scanning standards
GS1-issued vs. reseller-issued GTINs: a practical comparison
| Factor | GS1-issued GTINs | Reseller-issued GTINs |
|---|---|---|
| Prefix ownership | Registered to your company in GS1 databases | Registered to the reseller; ownership transfered to you upon GTIN purchase |
| Annual fees | Typically yes (varies by GS1 country/organization) | Usually one-time |
| GEPIR visibility | Yes—your company name searchable | No—reseller or no entry |
| Ownership verification | Passes cleanly | Will not pass against GS1 checks. Reseller ownership documentation may suffice |
| Validity | Universally valid structure | Valid structure if properly issued |
| Best for | Ownership verifying retailers, GDSN, brand-sensitive categories | Direct-to-consumer, cost-sensitive launches |
Neither option is inherently wrong. The practical difference lies in where and how thoroughly GTINs will be verified by a retailer before accepting a product into their store. For the vast majority of retailers, such verification does not extend beyond verifying that the barcode actually scans. For more context, see Marketplace guidance for GS1 alternatives.
Common pitfalls and how to avoid them
| Pitfall | Why it happens | Prevention |
|---|---|---|
| GTIN rejected for “already in use” | Previous owner used it; marketplace has memory | Buy from reputable sources; check databases before use |
| Listing suppressed after going live | Data mismatch discovered post-launch | Pre-verify all product data fields |
| Chargebacks for incorrect data | Weight/dimension errors in retailer system | Measure carefully; update immediately if packaging changes |
| Barcode unscannable in store | Poor print quality, wrong color contrast, quiet zone violation | Test print; use color legibility tools; follow ISO standards; consider purchasing a barcode verification test |
For more on validation failures, see Common validation errors.
Pre-launch checklist
- Each product variant has its own unique GTIN
- GTIN check digit validates correctly
- Barcode image meets minimum print specifications (resolution, quiet zones, dimensions)
- Product data feed prepared for target retailer/marketplace
- GTIN-to-product mapping documented internally
- If using reseller GTINs: researched whether target channel performs GTIN ownership check, and if so, whether reseller ownership document is sufficient for the check
- Test scan performed on physical printed label
- Product registered in relevant databases if desired
Further reading and resources
- GS1 GTIN standards
- GS1 US: What is a GTIN
- Barcodes Database — product visibility database
- IBN Verified — barcode verification guidance
- GTIN Validator and Check Digit Calculator
- Barcode Colour Legibility Simulator