Do I need a separate GTIN for every variant?

Yes. Every variant a customer can choose between — each size, color, flavour, or pack count — is a distinct tradable item and needs its own GTIN. Reusing one number across variants makes them indistinguishable at the till and in the retailer’s system.

This is where GTIN consumption gets underestimated at launch. A product in five colors and four sizes is twenty items plus their case configurations, and the company prefix has to be sized for that.

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