By, Shayna Teicher Before I offer some good rules for keeping your makeup bag free of un-fresh products, keep in mind there are a lot of “guidelines” out there for how often to pitch things, but your main rule of thumb should be to always get rid of anything that now smells, looks or feels different from when it was new, no matter how old (or new) it is (rancid lipstick, for example, often smells a bit like crayons). There is an exception to this, however- some natural creams (Like Sanre Organic Skinfood) can separate a bit as they don’t use any chemical emulsifiers. In these cases, simply stir it back up with a clean utensil to reincorporate. I’ve listed the product types below in order from most frequently replaced to longest lasting. *TIP: Hopefully you all know this one by now, buy it bears repeating- don’t pump your mascara wand, it simply incorporates air into the tube making it dry out faster and inviting bacteria in. To get more product on the wand, swipe it in a circular motion around the inside of the tube.
Dear Beauty Chick,…A lovely customer of mine recently asked me when she should throw out makeup (I’m pretty sure she was in the midst of a “spring cleaning bug” as one has hit me recently as well.) So naturally I said “That’s a great question- I’m so glad you asked!” 
As much as we hate to throw out cosmetics and skin care products we never got to use up, it’s even more important not to use something that’s “past its prime”. Open skincare and makeup can become contaminated with microbes, bacteria, etc over time and the result of using an old product can harm more than your wallet. Using expired or contaminated products can result in irritation, mild breakouts or even an infection.
Mascara: 3-6 months. If you’re using something with preservatives (like a department store brand) you can probably get away with closer to 6. For 100% natural ones (like Honeybee Gardens or Dr. Hauschka) better to play it safe and pitch after 3 months. 
Lip Gloss. 6-24 months. I’ve seen sources that say lip gloss is good for up to two years, which it probably is (if you use a clean applicator every time and never leave it in the sun or your car….). The germaphobe in me though, wants to replace my lip gloss every 2-3 months. If you use the same one or two colors every day, they probably won’t last you much longer than that anyway. So there you go, 3 months to two years (I know, not the written in stone answer you were looking for). This is one of those common sense things. If you’ve just battled a cold sore or the flu, probably best to get rid of whatever lip product you were using and get a new one. If you’ve been healthy and your lip gloss still smells, looks, tastes like new, gloss on!
Creams and Liquids: 3-12 months. These can be trickier, new types of packaging (like airless pumps) have greatly extended the shelf- life of some of these products up to a year, but products in open jars/bottles still don’t usually hold up more than 3-6 months. Again, your everyday practices make a big difference as well. If you’re super strict about always using a clean, sanitized brush in your pot of gel eye liner, for example, it’s going to last a lot longer than if keeping you don’t. These include gel & liquid eye liner, cream concealer, liquid foundation, cream eye shadow, etc.
Pressed & Loose Powders: 1-2 years. Most powders can keep for up to two years- whether or not there are preservatives will make a difference here. If you see a paraben or phenoxyethanol in the ingredients and you keep your tools clean, it’ll probably be good through two years. Likewise, loose powders (like pure mineral foundation) that are free of all oils, waxes, additives and preservatives are also good for a few years. Keys to telling if they’re bad are if they have a change in consistency or color or don’t apply as smoothly as they once did or start to feel “chalky”. Pressed powders can also get what looks like a hard “film” on the surface- a sign it’s time to throw it out These include eye shadows, pressed foundation, face powder, pressed & loose blush, etc. 
Pencils, Crayons & Sticks: 1-2 years. These guys can last a few years depending on the formulation and if you keep them clean and sharpen them frequently. But if the product seems drier, smells different or appears cracked or crumbly, it’s time to pitch it, no matter how old it is. This includes: lip pencils, eye liners, lip sticks, “crayons”, blush sticks, etc.
Originally Posted on Butterfly Effect Beauty’s Official Blog
