The open jar marked "12M" on a cosmetic means a 12-month period after opening. It doesn't mean 12 months after purchase, and it doesn't tell you how old the unopened product is. Record the opening date, keep any printed expiry date, and follow the product's instructions. A bottle with no visible date needs more checking, not an assumed lifetime. HPRA cosmetic label guide.
We reviewed regulator and dermatologist guidance on October 1, 2026. This guide explains US and EU labeling; it cannot establish whether an individual product in your makeup bag is still safe.
Read the mark before doing the date calculation
Several marks can appear on one package. They answer different questions.
| Mark on the package | What it tells you | What to record |
|---|---|---|
| Open jar with "6M," "12M" or another period | The period after opening, often shortened to PAO | The day you first open the product |
| Hourglass or wording such as "best used before end," followed by a date | The EU date of minimum durability under appropriate storage conditions | The printed date and any storage directions |
| Batch or lot code | An identifier used to trace the manufactured batch | The code, if you need to contact the brand |
| Open-book symbol | There is more information supplied with the product | Keep or photograph the accompanying information |
The hourglass, batch identifier and open-book meanings are described by France's consumer regulator, DGCCRF. The HPRA explains the open-jar symbol.
US and EU packaging follow different rules
In the US, cosmetics are not generally required to carry an expiration date or have a legally prescribed shelf life. Manufacturers remain responsible for product safety and for determining shelf life. The absence of a date therefore doesn't establish that the product lasts indefinitely. FDA cosmetic shelf-life guidance.
EU rules use a different approach. A minimum-durability date is required unless the product is stable for more than 30 months. For those longer-lasting products, the label generally gives a period after opening. There are exceptions when that concept doesn't apply, including single-use products and products that do not physically open. These exceptions need justification in the product information file. HPRA guidance, section 11.3.
The 30 months is a labeling threshold. It is not a promise that every unopened beauty product will last that long.
Keep an opening date you can find again
Put a small dated sticker on the container without covering its existing label. Alternatively, photograph the package and add the opening date to the image caption. The American Academy of Dermatology recommends tracking when you open cosmetics so you know when replacement is due. AAD guidance.
For example, a product marked "6M" opened on October 1, 2026, reaches six months on April 1, 2027. Set the reminder when you open it. Keep any separate printed expiry date in the same note; don't overwrite it with your calculation.
A useful record is short: product name, purchase date, opening date, printed date or PAO, and a photograph of the batch code. Name the shade too if you own several versions. This makes a later conversation with customer service much easier than sending a picture of a nearly illegible stamp.
Ask the brand about an unclear batch code
The HPRA describes a batch number as an identifier that supports traceability. It is separate from a product barcode unless that barcode changes for each manufactured batch. A code is not automatically a consumer-readable expiry date. HPRA guidance, section 11.6.
Treat a date returned by an unofficial lookup site as unverified until the manufacturer confirms it. Even a correctly identified manufacturing date would not tell you when you opened the bottle or how it was stored.
Send customer service the exact product name, code and package photos. Ask what the code means, what unopened shelf life applies, and what period after opening the brand specifies. If the code is ambiguous, ask for the date written out in words. Don't add a guessed three-year allowance to a number you cannot interpret.
Storage and visible changes both matter
Keep cosmetics in a clean, dry space at room temperature, away from direct sunlight, and close lids securely after use. The AAD advises discarding makeup that develops changes such as a bad smell, clumping, separation or a different color or consistency. Those are reasons to stop using it even when your calendar reminder is still months away. AAD storage and replacement advice.
Follow any more specific storage instructions on the label. The FDA warns that warm or damp conditions can favor microbial growth and damage preservatives. It also advises clean containers, washed hands and no sharing. Don't add water or saliva to revive a dried product: that can introduce microorganisms and dilute its preservatives. FDA microbiological safety guidance.
Use appearance and smell to flag a problem, not to cancel a replacement date.
Give mascara its own reminder
The FDA's eye-cosmetic guidance advises discarding mascara three months after purchase. It also says to stop using an eye cosmetic immediately if it causes irritation and seek medical advice if irritation persists. After an eye infection, discard eye cosmetics used when the infection occurred. These instructions can require replacement before a general PAO reminder. FDA eye-cosmetic advice.
Save the purchase date for mascara even if you track opening dates for the rest of your makeup.
Check sunscreen separately
US sunscreen is regulated as a drug. FDA rules require an expiration date unless stability testing shows the product remains stable for at least three years. Follow a printed expiry date. For sunscreen without one, the FDA says to consider it expired three years after purchase and to discard it if you don't know its age. FDA sunscreen guidance.
Write the purchase date on an undated sunscreen when you buy it. Protect the container from excessive heat and direct sun, as FDA storage guidance advises. For products bought outside the US, read their own labeling rather than applying a US rule automatically. Once you've checked the bottle, our guide to reapplying sunscreen over makeup covers the next practical step.
Cover image: AI-generated editorial illustration.
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