Here’s when you need to bin your favourite products.

Hands up, those who faithfully throw out their makeup and skincare products when they expire.

Now hands up, those who just chuck beauty products out when they’re finished with them.

NOW hands up, those who didn’t even realise their makeup had a use-by date at all.

From the discussions I’ve had around my workplace, I would say most people are in the latter two camps.

Makeup and beauty products do have very specific use-by dates, which can be found on the back of the product. Let me introduce you to the PAO symbol.

PAO stands for Period After Opening. The M stands for months, and the number on the little open jar is how many months. Pretty simple, huh?

But here’s where it gets tricky: the use-by date depends on the date the product is opened, and the conditions in which it’s stored. Make sure all your products aren’t exposed to heat and they should last their full shelf life.

But because I’m such a generous soul, and I want to spare your eyes from having to read the tiny print on the back of your products, I’ve put together a general guide on when’s best to chuck your products.

Mascara: 3-4 months

My mascara almost ALWAYS goes off before I get a chance to finish the tube, so I’ve taken to only buying small tester sizes that Mecca Maxima and Sephora sell. You know the ones; they’re located RIGHT next to the register so you’ll ponder picking up a few right before you get to the front of the queue.

“But my mascara lasts longer than three months and I’ve never had a problem with it!” I hear you crying. Listen, as a woman who has had five consecutive styes over just one week from bad mascara, I can tell you it just ain’t worth it. Not to mention more serous infections that can affect your sight.

Hot tip: if your mascara smells at all, even if it’s a chemical smell, it’s rancid and you need to bin it, STAT.

Foundation: 12 months

This use-by date will change big time depending on whether you use liquid or powder coverage. Liquids last for about 6-12 months because they’re full of moist, dark corners in the bottles, perfect for developing gross bacterial infections. Powders will last double that because the dry conditions don’t allow for nasties to form.

Concealer: 12 months

Bad concealers actually cause the blemishes you’re trying so hard to hide. In order to blend in smoothly with your skin, concealers are full of oils and shea butters that are prone to drying out. If your concealer cracks, smells different, or changes consistency at all, chuck it.

Micellar water: 6 months

The main ingredient in micellar water is WATER, so this one is obviously has a limited shelf life. Think: you wouldn’t drink water you’d left in a bottle for months on end, so you shouldn’t use it on your face either. The liquid breaks down on exposure to air and the moisture encourages bacterial growth. If you’ve had it longer than six months, get rid of it immediately.

Cleanser

The majority of cleansers are built to withstand a year of use, but depending on the ingredients this could change. Check the back of the bottle for this one.

Toner: 6-12 months

You can probably tell from the consistency of toner that the main ingredient for this one is also water. Fortunately, it has a longer shelf life than micellar water because of the extra product additions that help preserve the formula.

Eyeliner: 3-24 months

I know it’s your fave liquid liner, and I KNOW you probably spent half your rent on it but please don’t let it overstay its welcome. As with mascaras, the eye infections you can get from eye products gone bad are just plain nasty. Liquid should last a similar time to mascara, as they’re prone to the same bacterial infections. If you notice a change in consistency, smell, or colour, ditch it. Pencil liners are another story, lasting up to two years.

Lipstick: 2 years

Look after your lipstick well and it will look after you for much longer than most of your other products. Keep the lid on (and don’t let it roll around the bottom of your back with all the lint and discarded gum wrappers, obv). Using a lip brush will prevent contaminating it with your mouth germs more often than necessary, and when in need, wipe it with a makeup wipe to disinfect.

Perfume: 8-10 Years

These babies have STAYING POWER. As long as you keep away from heat, bright light and keep the lid on, this will last up to a decade. This is pretty much a justification to collect ALL THE PERFUME BOTTLES and hoard them on a beautiful dresser. Tell everyone I gave you permission.