Barcodes are one of those details that seem unimportant until a listing is rejected or a warehouse cannot receive your stock. On TikTok Shop, some categories and markets ask for a product identifier such as a GTIN, UPC or EAN, while others treat it as optional. Warehouses, 3PLs and platform fulfillment programmes also rely on barcodes to identify products quickly and accurately.
This guide explains what these identifiers are, when you need them, how to get legitimate ones and how to handle variants and errors. Requirements differ by market and category and can change, so check the product identifier rules in your Seller Center.
GTIN, UPC, EAN and ISBN Explained
- GTIN (Global Trade Item Number) is the umbrella term for global product identifiers.
- UPC is a 12-digit GTIN commonly used in the United States and Canada.
- EAN is a 13-digit GTIN commonly used in Europe, the UK and many other regions.
- ISBN is a GTIN for books.
All of these identify a specific product, in a specific variant and pack size, from a specific brand owner. The barcode printed on packaging is simply a scannable version of the number.
GTIN vs Seller SKU
A GTIN and a seller SKU are different things. The GTIN is a global identifier that stays the same wherever the product is sold. The seller SKU is your internal code for inventory and integrations. Every sellable item should have a unique seller SKU; many should also have a GTIN. Our guide to SKUs and variants explains seller SKU codes.
When TikTok Shop Asks for a Barcode
Depending on market and category, the product identifier field may be required, optional or not shown. It is more likely to be required for branded goods sold widely in retail, electronics, health and beauty, and products in categories where counterfeits are common. Where a barcode is required and you do not provide a valid one, the listing may be blocked or rejected.
Even when optional, providing a valid GTIN can help the platform match your product correctly and supports trust in the listing.
Where to Get Legitimate GTINs
The official source of GTINs is GS1, the global standards organisation, through its national member organisations. Brand owners license a company prefix and assign numbers to their products. This links the barcode to your company, which is what marketplaces and retailers increasingly check.
Cheap barcodes sold by resellers may have been issued to another company years ago. Marketplaces can detect that the number does not belong to your brand, which can cause rejections or later problems. For a brand you intend to grow, buy GTINs from GS1 directly.
Barcodes for Variants and Pack Sizes
Each distinct sellable item needs its own GTIN. That means each colour, each size and each pack quantity typically has a different barcode. A single t-shirt in five sizes and four colours needs twenty GTINs. A product sold as a single unit and as a three-pack needs separate GTINs for each.
Keep a barcode register that maps every GTIN to its seller SKU, product name and variant. This register prevents duplicate assignment and helps warehouses receive stock correctly.
Reselling Other Brands' Products
If you resell products made by another brand, use the barcode the manufacturer printed on the packaging. Do not create your own GTINs for another brand's products. You may also need brand authorisation documents. See our guide to brand and category qualifications.
Exemptions for Products Without Barcodes
Handmade items, private label products without barcodes, bundles you create yourself or some unbranded goods may not have GTINs. Some markets allow an exemption or a no-barcode option for such products, sometimes with an application. Exemptions are not universal, so check whether your market offers one and what evidence is needed. If you plan to sell through retailers or platform fulfillment later, getting GTINs from the start is usually simpler.
Barcodes for Bundles
A bundle you assemble yourself, such as a gift set of three products, is a new sellable item. Depending on the rules, it may need its own GTIN as a bundle, or be exempt. Your warehouse also needs a way to identify it, either a bundle barcode or a kit instruction. Our bundle listings guide covers the setup.
Barcodes and Warehouses
Warehouses, 3PLs and platform fulfillment centres scan barcodes when receiving and picking. Products without scannable barcodes may need labels applied, sometimes for a fee. Some programmes use their own labels instead of or on top of manufacturer barcodes. Check your fulfillment partner's labelling requirements before shipping stock. Our fulfillment options guide explains the models.
Printing and Placing Barcodes
Barcodes must be printed clearly at a scannable size, with enough white space around them and good contrast. Place them on a flat surface of the outer packaging where they are easy to scan. Test-scan new packaging before a full production run; a barcode that will not scan causes receiving delays and picking errors.
Common Barcode Errors
- Invalid check digit: the last digit of a GTIN is calculated; a typo makes it invalid.
- Duplicate GTIN: the same number used for two different products or variants.
- Number not linked to your brand: often from barcode resellers.
- Wrong format: extra spaces, missing leading zeros or the wrong number of digits.
- Barcode on listing does not match packaging: causes warehouse and customer confusion.
Our guide to common Seller Center errors covers more fixes.
A Worked Example: Launching a Private Label Range
A new private label kitchenware brand plans eight products, each in two colours, for sixteen sellable items. Before printing packaging, the founder licenses a GS1 company prefix, assigns sixteen GTINs and records them in a barcode register alongside each seller SKU. The barcodes are printed on packaging and test-scanned. In Seller Center, each variant's GTIN is entered in the product identifier field. When the brand later moves stock to a 3PL, receiving is fast because every box scans correctly, and the listings never face barcode-related rejections.
Keeping Barcode Data Consistent Across Channels
If you sell on several channels, the same product should carry the same GTIN everywhere: TikTok Shop, your website, Amazon and retail partners. Consistent identifiers help platforms recognise your product as the genuine brand listing and make reporting across channels easier. Keep the barcode register as the single source of truth, and update every channel when you introduce a new variant or retire an old one. Never reuse the GTIN of a discontinued product for a new item; standards bodies have rules about reuse, and reusing numbers causes confusion in warehouses and marketplaces long after the old product is gone.
When you change packaging but not the product itself, the GTIN normally stays the same. When you change the product in a way customers would notice, such as a new formula, size or pack quantity, it usually needs a new GTIN. Check the rules from your GS1 member organisation if you are unsure.
Barcode Checklist
- Check whether your category and market require product identifiers.
- License GTINs from GS1 for your own brand.
- Assign a unique GTIN to every variant and pack size.
- Keep a barcode register mapped to seller SKUs.
- Use manufacturer barcodes when reselling other brands.
- Test-scan packaging before production.
- Check fulfillment partner labelling rules.
Desnora helps brands prepare compliant catalogs for TikTok Shop. Explore our TikTok Shop services or get in touch.
Frequently Asked Questions
Do I need a barcode to sell on TikTok Shop?
It depends on market and category. Some require a product identifier; others treat it as optional.
What is the difference between a UPC and an EAN?
Both are GTINs. UPC has 12 digits and is common in North America; EAN has 13 digits and is common elsewhere.
Where should I buy GTINs?
From GS1 through your national member organisation, which links the numbers to your company.
Can I use cheap barcodes from resellers?
It is risky. They may be registered to another company, which can cause rejections or later problems.
Does each variant need a different barcode?
Yes. Each colour, size and pack quantity is a different sellable item and usually needs its own GTIN.
Is a GTIN the same as a seller SKU?
No. A GTIN is a global identifier; a seller SKU is your internal code.
Can I get an exemption from barcodes?
Some markets offer exemptions for handmade, private label or unbranded items. Check your market's rules.
What barcode do I use when reselling another brand?
Use the manufacturer barcode printed on the packaging. Do not create new GTINs for another brand's products.
Why is my barcode marked invalid?
Common causes are typos that break the check digit, missing leading zeros, wrong length or duplicates.
Do warehouses need barcodes?
Yes. Warehouses scan barcodes to receive and pick stock, and unlabelled items may need labelling for a fee.
Does new packaging need a new GTIN?
Usually not if the product itself is unchanged. A new formula, size or pack quantity normally needs a new GTIN, so check GS1 guidance.
Can I reuse an old GTIN for a new product?
Avoid it. Reusing numbers from discontinued products causes confusion in warehouses and marketplaces and may break standards rules.
Should I use the same GTIN on every sales channel?
Yes. The same product should carry the same GTIN everywhere, which helps platforms recognise genuine brand listings.