Cosmetic expiry dates and storage

The expiry date tells you how long a product stays safe from manufacture, while the period after opening tells you how long it lasts once opened. Korean cosmetics show one or the other, and when the period after opening is used, the manufacture date is printed too. Follow whichever limit comes first.

It means the product should be used within 12 months of opening; 6M means six months and 24M means 24 months. This symbol is common on products from many countries. Since it is easy to forget when you opened something, try writing the opening date on the container with a marker or a small sticker.

If a manufacture date appears alongside a period-after-opening symbol, follow the after-opening period and avoid products that have been sitting for a very long time. If you are unsure, contact the manufacturer with the batch number and ask. Regardless of dates, do not use a product that looks or smells wrong.

Yes. Even sealed products can change over time, so it is best to follow the printed expiry date. Storing them somewhere hot or humid for long periods can speed up deterioration. If you stock up, use the oldest items first and keep the rest in a cool, dry place.

It is not recommended. After expiry, preservatives may weaken and ingredients may break down, raising the chance of irritation, breakouts or contamination. Sunscreens and other functional products may also become less effective, so it is safest to throw out anything past its date.

Suspect spoilage if a product smells sour or different, changes color, separates into oil and water, or develops lumps. Throw it out immediately if you see spots that look like mold. Even if it looks fine, stop using it if it suddenly causes stinging or breakouts.

Most cosmetics are fine at cool room temperature away from direct sunlight. Products that need refrigeration usually say so on the package, so follow that guidance only when it is given. Moving products in and out of the fridge repeatedly can cause temperature swings that make some formulas separate.

Best avoided. A car in summer can get extremely hot, which can melt or separate formulas and degrade ingredients in products like sunscreen and perfume. Items you carry every day, such as cushion compacts and lipsticks, should not be left in a hot car or bag for long periods.

Bathrooms see big swings in temperature and humidity, making them a poor storage spot for skincare. Leaving lids open there lets moisture and bacteria in more easily. Keep cleansers and other shower-use items tightly closed, and store everything else in a cool, dry room.

If the period after opening has passed, or the bottle was stored in heat, it is better to buy a new one. Sunscreen filters can degrade, meaning you may not get the protection shown on the label. Even within the stated period, skip it if the smell, color or texture has changed.

Because the wand touches your eye area and pushes air and bacteria into the tube, mascara should be replaced relatively often. Check the period-after-opening symbol, and replace it sooner if it dries out or smells odd. If you have had an eye infection, it is safest to throw away the eye makeup you were using.

Lip products touch your lips and saliva directly, so they can become contaminated and should be used within the stated period after opening. Replace them if they develop a rancid, oily smell or if beads of moisture or white spots appear on the surface. Avoid sharing lip products with others.

Puffs collect oil and makeup, which makes them a breeding ground for bacteria, so wash them often and let them dry completely before reuse. Replace a puff if it still smells after washing or has lost its bounce. Keeping a spare and rotating two puffs makes hygiene much easier.

Store sheet masks in a cool place away from direct sunlight and use them before the printed expiry date. Once a pouch is opened, use the mask right away rather than saving leftover essence for later. If a pouch looks swollen or the mask smells strange, do not use it.

Single-use sample pouches are usually meant to be used in one go, so finish them as soon as possible after opening. Leaving an opened pouch for days exposes the contents to air and bacteria. Unopened samples have expiry dates too, so check them before use, especially if they have been sitting in a drawer.

Dipping your fingers into a jar can introduce bacteria, so using a clean spatula is more hygienic. If you do use your fingers, wash and dry your hands thoroughly first. Close the lid right after use to keep air and dust out of the product and help it stay fresh until the end.

Pumps and tubes limit contact with hands and air, which helps reduce contamination and oxidation. That is why they are common for products with light- or air-sensitive ingredients. If you use jar packaging, a spatula and closing the lid promptly make a real difference to how long the product stays in good condition.

Perfume is sensitive to light and heat, so keep it in a cool place out of direct sunlight. Storing it in its original box helps block light. If the scent turns sour or the color changes noticeably, the fragrance may have degraded, so test it before spraying it on your skin.

The usual approach is to wipe out leftover product with tissue, then separate the container and its parts by material and sort them according to your local recycling rules. Parts that are hard to take apart or mix several materials, such as pumps, often go in general waste. Check your local district office's guidance for exact rules.

Products with few or no preservatives can spoil faster after opening, so they may carry a shorter period after opening. That is why they often come in small sizes or single-use packaging. Follow the package directions, store them somewhere cool and use them up quickly.