What You Really Need to Know About Makeup Expiration Dates

We know it’s a tough call throwing away your favorite blush or lipstick, but abiding by makeup expiration dates is actually incredibly important. Why? Cosmetics can trap bacteria, which means replacing them regularly is necessary to try to avoid skin irritation, breakouts, eye infections, and styes. Not pretty, right? According to makeup artist Ashely Rebecca, “Skin irritations such as rashes, bumps, and burning sensations can occur when using expired products. If you use mascara or eyeliner that’s past its expiration date, you can experience swelling, itchiness, or redness. It’s always best to see a dermatologist immediately if you experience any kind of reaction.” (And it’s not just your makeup formulas—check out what happened when we tested bacteria levels on makeup brushes).

But here’s a caveat: Unlike the contents of your fridge, the use-by date on your makeup products relies on the first day you use them, not the purchase date. “If you’re ever stuck wondering, all products have a small symbol that look like a jar with a number/letter on the inside, ex: 12M. This means, usually, that a product has a 12-month shelf life upon opening,” says celebrity makeup artist Britty Whitfield. “For makeup, I always follow what the time frame is in the symbol. The worst possible thing would be to use an old, oxidized foundation.”

So how do you know when to toss that foundation or mascara? Separation or changes in texture along with foul smells are dead giveaways the product has gone bad.

While it’s crucial to look out for those telltale signs, it’s still helpful to get a general idea of how long each product is meant to last. Keep reading to learn the makeup expiration dates for every kind of cosmetic, from blush to eyeliner.