Why it should come from GS1
Retail barcodes (EAN-13, also called GTINs) are issued by GS1. Shops and Amazon check barcodes against the GS1 database, and numbers bought cheaply from resellers often fail that check. Join GS1 UK and you get a company prefix and a block of numbers to assign yourself. Check GS1 UK for current fees.
Each variant needs its own number: a different flavour, strength or capsule count is a different product.
How big it must be
The standard EAN-13 at 100% size is about 37.29 × 25.93 mm including the quiet zones and the numbers underneath. For retail tills, GS1 allows 80% to 200% of that size. Don’t cut the height down, as truncated barcodes often fail to scan.
Keep the quiet zones clear: a blank space of 11 bar widths on the left and 7 on the right.
Placing it on a bottle
- On small round bottles, turn the barcode so the bars run horizontally (“ladder” orientation). Bars that wrap round the curve can distort and fail to scan.
- Print it in black or dark blue on white. Red, orange and yellow bars don’t scan, because scanners use red light.
- Keep it away from the label join and seams.
- Ask for a scan test on your proof.
Not legal advice. This guide covers the general rules for food supplements sold in Great Britain. Check your own product with a regulatory adviser, your local Trading Standards team or your Primary Authority partner.