How To Know When Makeup & Skincare Expire! There’s a date that’s typically on the bottom or back of your makeup or skincare product that tells you how long it’s good for after it’s opened. For example, 6M means it’s good for 6 months after opening or 12M means it’s good for 12 months after opening the product. Sometimes there is an additional full-on expiration date that’s on the outside of your packaging. This is typically for products with sunscreen or products that expire by a specific date regardless of when you open them. I’ve linked makeup and skincare favorites! beauty tips, beauty hacks, beauty favorites LTKbeauty LTKunder100 LTKunder50