How to Read a Batch Code

Almost every genuine cosmetic carries a batch code: a short string, usually stamped or laser-etched rather than printed on the label. It is how a manufacturer traces a production run, and it is one of the few things a counterfeiter frequently gets wrong.

Where to look

• Stamped into the crimp at the bottom of a tube
• Etched into the base or shoulder of a bottle
• Printed directly on the carton, often near the barcode

It is usually 4 to 10 characters, mixing letters and digits. It is not the barcode, and it is not the long printed text on the label.

What it tells you

Most codes encode a factory and a production date. The format differs by manufacturer, so there is no single rule — but there are free batch-code checkers online that cover many of the large brands and will return a manufacture date.

That date matters because cosmetics have two different lifespans:

• Shelf life — how long it lasts unopened, typically two to three years from manufacture
• Period after opening — the little open-jar symbol with "6M" or "12M" on it, which starts the day you unseal it

A product made four years ago is not necessarily unsafe, but it is not what you paid for either.

What it tells you about authenticity

On its own, not much — a code can be copied. What is informative is when it is wrong:

• No batch code at all on a product from a brand that always uses one
• A code printed on a sticker rather than stamped into the material
• A code on the box that does not match the code on the bottle inside
• A code that a checker cannot parse at all, for a brand it otherwise covers

Any of those is a reason to stop and ask the seller.

Ask before you buy

A seller who knows their stock can tell you the batch code before you order. One who cannot, or who will not, has told you something.

This is the part of our own process we are building the site around: we record the batch code of every consignment, along with where it came from, and show it on the product page. Where we do not hold a field, it stays blank rather than being filled in to look complete.