Cosmetic Batch Codes: What They Are and How to Create One

A cosmetic batch code is a short identifier on a product's label that lets you trace it back to the specific production run it came from. UK law requires one on every cosmetic — soap, bath bombs, lip balms, moisturisers — so that if there's ever a safety problem, the affected products can be identified and traced. You design the format yourself; what matters is that the code reliably links the product to your records.

This guide explains what the law actually requires, what makes a good batch code, and how to set up a simple system that works whether you make two bars a month or two hundred.

This covers GB (Great Britain) cosmetic requirements. Northern Ireland follows EU Cosmetics Regulation. This is not legal advice.

What the Law Requires

The batch number is one of the mandatory label elements under the UK Cosmetics Regulation (retained Regulation (EC) No 1223/2009). The gov.uk guidance on the regulation puts the requirement plainly:

"A code which enables the manufacturer or supplier to identify the batch in which the product was manufactured must be marked on both the primary container and outer packaging. If the product is not made in a batch, then the code should enable the date and place of manufacture to be identified."

Two things to take from that:

1. It goes on both the container and the outer packaging (where there is outer packaging). The batch code is one of the elements that must stay on the product itself, not only on a box that gets thrown away.
2. If you don't make in batches, the code must instead identify the date and place of manufacture. So a one-off product still needs a traceable code.

The batch code sits alongside the other required cosmetic label elements — responsible person details, INCI ingredient list, nominal content, best-before or PAO symbol, product function, and any precautions. Our cosmetic labelling requirements guide covers all of them.

Why It Matters

The batch code is the thread that ties a product on a customer's shelf back to how it was made. That matters in three situations:

• A safety problem or recall. If a customer reports a reaction, or you discover a contaminated ingredient batch, the code lets you identify exactly which products are affected — rather than recalling everything you've ever made.
• An adverse event investigation. If a serious undesirable effect is reported and the authorities investigate, traceability to the batch is part of demonstrating you took proper care.
• Your own quality control. When something goes wrong (a batch that won't set, a scent that faded fast), the code helps you find the common cause in your records.

A batch code with no records behind it is just a number. The point is the link to your batch records — what ingredients went in, from which supplier lots, on what date.

How to Design a Batch Code

There's no required format. You can use any system that lets you uniquely identify a production run and trace it to your records. Common approaches:

Date-based. Encode the date of manufacture: 240722 for 22 July 2024, or 2024-07-A for the first batch in July 2024. Simple, and it doubles as a manufacture-date reference for non-batch products.

Sequential. A running number: B-0042 for your forty-second batch. Easy to read, but you have to keep a separate log mapping each number to its date and contents.

Combined. Date plus product plus run: LAV-240722-01 for the first lavender soap batch made on 22 July 2024. More informative at a glance, slightly longer on the label.

Whichever you choose, keep it:

• Unique per batch — never reuse a code.
• Short enough to print legibly on a small label.
• Documented — maintain a batch log linking each code to its date, ingredients, supplier lot numbers, and quantity made.

What to Record Against Each Batch

The code is only as useful as the records behind it. For each batch, log:

• The batch code itself
• Date of manufacture
• Product name and recipe version
• Each ingredient used, with the supplier's own lot/batch number
• Quantity produced
• Any notes (substitutions, issues, test results)

Keep these records as part of your wider compliance file. For cosmetics, you must maintain a Product Information File (PIF) for each product — the batch records support it.

Batch Codes vs Best-Before / PAO

A batch code is sometimes confused with the best-before date or the period-after-opening (PAO) symbol, but they're separate elements:

Element	What it tells you
Batch code	Which production run the product came from (traceability)
Best-before date	The date until which the product stays in good condition (for products lasting under 30 months)
PAO symbol	How many months the product is safe after opening (for products lasting over 30 months)

All three can appear on the same label, and most cosmetics need the batch code plus one of best-before or PAO. Our cosmetic labelling requirements guide explains when each durability marker applies, and the free Cosmetic Labelling Checker flags any required element your label is missing.

A Note for Candle and Wax Melt Makers

If you make home-fragrance products rather than cosmetics, batch coding works the same way in principle but the legal framework is different — candles and wax melts fall under GB CLP, not the Cosmetics Regulation. Good batch records are still strongly advisable for traceability and your general product-safety duty, even where CLP doesn't prescribe a batch code the way the Cosmetics Regulation does.

FAQ

Is a batch code a legal requirement on cosmetics in the UK?

Yes. Under the UK Cosmetics Regulation, a code identifying the batch must be marked on both the container and outer packaging. If the product isn't made in batches, the code must instead identify the date and place of manufacture.

What format should a cosmetic batch code be?

There's no prescribed format. Use any system — date-based, sequential, or a combination — that uniquely identifies each production run and links it to your records.

Where does the batch code go on the label?

On the product itself (the primary container) and, where there is one, on the outer packaging. It needs to stay with the product, not only on packaging the customer discards.

Related Guides

• Cosmetic labelling requirements UK: a plain-English guide
• Soap and cosmetics safety assessments: what UK makers need to know
• Cosmetic safety solutions for UK makers

Sources

• GOV.UK — Regulation 1223/2009 and the Cosmetic Products Enforcement Regulations 2013 (Great Britain)
• GOV.UK — Making Cosmetic Products Available to Consumers in Great Britain