Cosmetics—unlike books and photos—aren't meant to last forever. (Do you really want expired products on your face, anyway?) In the best-case scenario, they won't work as well as they once did. (Think: flaky mascara, goopy gloss or streaky foundation.) In the worst-case scenario, you could end up with an infection. (Sties, breakouts and the like.) Here, a quick guide on when everything should go in the trash.

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Liquid Foundation: After 6 months to 1 year

Whether you use your fingers or a brush, chances are you're not washing either every time you apply your foundation, right? No judgment here, but you are introducing bacteria to the formula with each use. Don’t let it fester.

Cream Makeup: After 6 months to 1 year

We’re talking concealers, blushes and shadows. Texture is everything when it comes to cream formulas. If it looks or feels clumpy, toss it out. And pay special attention to cream shadows, which should be replaced more often (given how close they come in contact with your eyes).

Lipstick: After 1 year

If you notice that your favorite lipstick isn’t spreading like butter anymore, it's time to let go. If it is gliding on smooth, keep it that way and store it in a cool, dry place (#1 spot: your fridge) and not, say, your car's cup holder.

Powder Makeup: After 2 years

Powder blushes, setting powders and highlighters are the gifts that keep on giving. Clean your makeup brushes and your compacts often to make them last even longer. (Here’s how.)

Eyeliner: After 3 months (liquid); After 2 years (pencil)

Fresh liner equals a perfect line every time. (A steady hand also helps.) Gel or liquid formulas dry out fairly quickly so if you’re looking to save money, this is where you skimp. Keep pencil liners sharpened and out of humidity (aka out of your bathroom) and they can last for up to two years.

Mascara: After 3 months

Just like with liquid liners, these puppies dry up quick. And if you recently had an eye infection of any sort, drop that wand lest you want another case of conjunctivitis.

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Face Moisturizer: After 6 months (tub); After 1 year (pump)

Scoop out creams with a fresh Q-tip—not your fingers—before applying it to skin. Prefer a pump? Avoid direct contact with the spout to prevent contamination.  

Sunscreen: After 1 year

Two words: expiration date. Since the whole purpose of sunscreen is to protect your skin from UV damage, it’s especially important to keep an eye on this often ignored date. Also, if you’re using the recommended amount (enough to fill a shot glass for your face, neck, tops of ears and décolleté alone), then a bottle shouldn’t last you more than one season, anyway.

Nail Polish: After 1 year

Contrary to old wives’ tales, out-of-date lacquer won't infect your cuticles or make your nails brittle, but it will streak and give you those dreaded bubbles. Buy a new bottle every fall/winter (and then every spring/summer) and live a little.

Perfume: After 8 to 10 years

Some fragrances can last up to a decade. (Thank God, because Tom Ford don't come cheap.) Keep your eaux de favorites out of sunlight and humidity to retain their original scent.

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