Internal barcode or GS1 number: which one do you need?

The real question is not the format, it is where the code will be scanned

People think the decision is between EAN-13, Code 128 or ITF-14. That is not where it is made. A barcode is only a drawing that encodes digits: any scanner reads it, whatever the format.

What decides is the identity behind the digits. Either the number was issued to you, and it is unique worldwide. Or you built it, and it is only worth something inside your own walls. Both scan equally well; they are not used in the same places.

What each one actually allows

An internal code sits in the range GS1 reserves for in-store use — prefixes 20 to 29. That range exists precisely so that businesses with no need for a worldwide number are not forced to obtain one.

What if I make up a company prefix?

This is the most common temptation, and the most expensive. The code will print, it will scan, and nothing will warn you. The problem appears later, in two places.

At listing time first. Marketplaces cross-check every code against the GS1 database and verify that the company prefix matches the brand owner. Amazon states it plainly: a code that does not match the information provided by GS1 is treated as invalid. Since 2016, codes bought from third-party resellers are rejected for that reason. Large retailers run the same check.

In someone else's business next, which is worse. A prefix belongs to a real, named company. Borrowing it risks issuing a number one of their products already carries: the wrong item at the wrong price at the till, stock records mixed together, and a product recall that cannot be traced.

Making up a prefix gives you nothing an internal code does not already give you. In a small shop both work; in retail both are refused. The only difference is the risk taken on someone else's behalf.

The internal code: what it really covers

It is often presented as a fallback. For most businesses that is wrong. If you manage your own shelves, your own stock and your own equipment, an internal code does exactly the job: free, immediate, no registration, no expiry.

It stops being enough the day your product has to be scanned by somebody else. A producer supplying shops is in that situation from the first order.

When GS1 membership becomes unavoidable

As soon as the code must be read outside your own business: a supermarket, another shop, a distributor, an online marketplace, an export customer. In every one of those cases, the other party checks that the number is registered.

Membership goes through a GS1 organisation against an annual fee. Prices and steps differ by country, so ask the office that covers yours rather than trusting a figure found elsewhere.

What if my country has no GS1 office?

Several countries in Central Africa are in this situation — the Republic of the Congo, Gabon, Chad, the Central African Republic and Equatorial Guinea have no national GS1 organisation. GS1 says so on its own country pages.

Two routes remain open. You can register with the office of another country — for francophone Central Africa, GS1 Cameroon is the nearest. Or with GS1 Global Office, which exists precisely to serve companies in countries without a local office. Either way, the prefix you are given belongs to you alone.

In the meantime, an internal code gives you a complete number today, free, usable throughout your own business.