The Best Way To Tell If Your Foundation Is Expired

We live in a makeup storm. Many new makeup products are released every day, and they're all available in-store or from the comfort of your smartphone or computer. With the many hauls and the sheer amount of makeup you probably own, it can be challenging to track what products are still suitable for use and which ones need to be thrown out or replaced. One makeup product that is a frequent favorite in our routine but has the reputation of barely getting checked for expiration is none other than foundation.

Now, it may be tempting to keep your foundation tucked away in your makeup bag, even when you might have had it for a bit over two years. But, most foundations contain ingredients like colorants, emulsifiers, and fillers, which have wax or oil as their base (via WebMD). These ingredients can separate over time into layers once expired. If used while separated, you could be applying high concentrations of comedogenic oils onto your skin, which can lead to conditions like acne cosmetica (via Sk:n). To prevent certain skin conditions and help with your much-needed clean-out, here are a few ways you can tell your foundation is fit for the bin.

Key beauty tip: learn to understand the information on the back of your products such as the ingredient lists, the batch number, and even the open jar icon with a number and the letter M on it. This symbol is the period after opening (PAO) symbol. The PAO symbol indicates the shelf life, which, according to Shure Cosmetics, is the length of time your product will last after you open it. For example, 12M on the small jar indicates that the product will last 12 months after opening. The same goes for 3M, which means three months after opening, and 6M, which means six months.

Cosmetics, foundations included, contain a preservative system, chemicals that keep them safe and stable for use for a period of time (per The Eco Well). Once this period elapses, the preservative system becomes compromised, and your product becomes unsafe for use. Thus, it's essential to be aware of how long your foundation's shelf life is and discard it once its time is up. Water-based liquid foundations usually have a shelf life of 12 months, while oil-based ones run for about 18 months (via MasterClass). Other indicators of shelf life are an expiration date right next to your foundation's batch number, which signifies how long the product will last while unopened (via CPT Labs). Regardless, checking for shelf life is the best way to tell if your foundation has gone bad.

Expiration dates and the period after opening (PAO) symbol are great indicators of expired makeup. Yet, microbes such as fungi and bacteria in the air and on your hands can get into your foundation. These microbes disrupt the preservative system, especially in foundations that are not in airtight packaging. With this, your foundation can cause skin infections, allergies, and irritation, and it does not last as long as it should (via Cleveland Clinic's Health Essentials). Foundation can also go bad due to oxidation, a reaction that occurs when exposed to air. To tell if your foundation has gone rancid before its expiry date, you should check for changes in smell, texture, and color (via Healthline).

If your foundation has a bad or "off" smell, it's no longer fit for use. An unusual smell from your foundation, whether powder or liquid, indicates a breakdown in the preservatives used. If the texture of your foundation has changed as well, from silky to clumpy, it's a good sign you should bin it. The separation of your foundation into layers is also a sign you need to let the product go. And if you notice your foundation has changed color, looks a bit more orange, or has gone a couple of shades darker, it's time to let it go. Oxidation has most likely occurred. Naturally, we always want to get the most out of our products, but using expired foundation will only harm your skin and ruin your makeup.