Does Sunscreen Expire? Period-After-Opening Dates for Sunscreen, Skincare and Makeup, and How to Track Them on Android

The bottle of sunscreen from last summer is still half full, so you use it, and get burnt. The mascara has been open since a wedding you barely remember, and your eye is itchy. The expensive serum says nothing about a date at all. Cosmetics and sunscreen are the one category of things with an expiry where almost nobody tracks the date, partly because the labelling is confusing and partly because the products sit around for years. This post explains the two kinds of dates on a cosmetic label, how long the common products actually last once opened, and how to set up reminders for them on an Android phone in a few minutes.

The two dates on a cosmetic: expiry and period after opening

A packaged cosmetic can carry two different clocks. The first is a printed expiry or best-before date, the kind you are used to from food: a day, month and year (often as an hourglass symbol with a date beside it) after which the maker no longer guarantees the product. The second is the period after opening, or PAO: a small open-jar symbol with a number and the letter M inside or beside it, such as 6M, 12M or 24M. That number is how many months the product is good for once you open it, regardless of the printed date.

The two interact in a way that catches people out. A moisturiser with a best-before of 2028 and a 12M jar symbol, opened today, is done next October, not in 2028. In the European Union, products with a shelf life over 30 months are not required to carry an expiry date and show the PAO symbol instead; products with a shorter shelf life must show the date. That is why so many creams and lotions have only the open jar and no date at all: the date is whatever day you opened it, and you are the only person who knows it.

Does sunscreen expire?

Yes, and it matters more than for most cosmetics, because the failure is invisible. The UV filters in sunscreen degrade over time and faster with heat, so an old bottle looks and smells fine while protecting you less than the SPF on the label. In the United States the FDA regulates sunscreen as an over-the-counter drug and requires an expiration date on the package unless the manufacturer's stability testing shows it stays effective for at least three years; a sunscreen with no printed date can be treated as good for three years from purchase. Many sunscreens also carry a PAO of 6M or 12M for the opened bottle.

Three practical rules follow. First, write the date you opened it on the bottle, or log it, because the PAO clock starts then. Second, a bottle that spent the summer in a hot car or a beach bag has aged faster than its date suggests; if it has separated, changed colour or smells off, bin it. Third, if you are not getting through a bottle in a season, buy smaller bottles. Sunscreen is the product where 'probably still fine' is a bad bet.

How long common products last once opened

The PAO on your own product beats any general table, so check the jar symbol first. Where there is no symbol, these are the typical ranges manufacturers and dermatologists quote, and they are driven mostly by how often the product touches your skin or eyes and whether it contains water (which bacteria need) or is a dry powder (which they do not):

• Mascara and liquid eyeliner: 3 to 6 months. Shortest of all, because the wand goes from your eye back into the tube every day. Replace sooner after any eye infection.
• Liquid foundation, concealer, BB and CC creams: 6 to 12 months.
• Sunscreen (opened): 6 to 12 months by PAO, within the printed expiry if there is one.
• Moisturisers, serums, eye creams: 6 to 12 months for jars you dip fingers into, often longer for pumps and airless packaging; vitamin C and retinol products degrade faster and usually say so.
• Lipstick and lip balm: 12 to 24 months.
• Powders (eyeshadow, blush, setting powder): 24 months or more, unless they develop a hard film or a smell.
• Nail polish: 1 to 2 years; it is unusable long before it is unsafe.
• Perfume: 3 to 5 years if kept out of light and heat; it changes rather than spoils.

Whatever the number, the universal signs to stop using something are a change in smell, colour, texture or separation that does not shake back in, and any product that goes near the eyes after an infection. Clean hands and closed lids extend every range above; a jar on a steamy bathroom shelf shortens it.

Tracking cosmetic expiry on Android

The problem with PAO is that it needs a date you have to record yourself, on the day you open the product, for an item you will not think about again for six months. That is exactly what a reminder app is for. Expiry Date Tracker is a free Android app (Android 7.0 or later) built for food, medicine and cosmetics; here is how to use it for a bathroom cabinet.

• Add the item the day you open it. Tap Scan barcode and point the camera at the box or tube: if you have scanned it before, the name fills in from your history, and new barcodes are looked up in the free Open Food Facts database. That database is food-focused, so expect many cosmetics to come back without a match. No barcode, or no match? Tap Add by hand and type a name like 'Mascara (black, opened Oct)'.
• Set the date from the PAO, not the printed expiry. The quick chips are +1w, +2w, +1m, +3m, +6m and +1y. For a 6M mascara tap +6m; for a 12M sunscreen tap +1y and nudge it back with the minus button, or type the date as YYYY-MM-DD. If the product has both a printed expiry and a PAO, enter whichever comes first.
• Pick a location. The chips are Fridge, Freezer, Pantry, Medicine and Other; Other is the one for the bathroom. You can add a note like 'bathroom cabinet, top shelf' and a quantity if you keep spares.
• Choose the warning. In Settings, reminders can fire 7, 3 or 1 day before (each also reminds you on the day), or on the day only, at 07:00, 08:00, 09:00, 12:00, 18:00 or 20:00. For cosmetics, 7 days before is the useful one: enough time to buy a replacement before the old one runs out.
• Tick it off when it is gone. Marking an item used cancels its reminders. If you replace it with the same product, scan the barcode again and the name is instant.

The list is grouped into expired, expiring today, this week and later, so the mascara that is due surfaces at the top even if you have forty food items in the same list. Reminders are scheduled on the phone itself, so they work with no signal, and there is no account, no sign-up and no cap on the number of items. It is free with a small banner ad, with a one-time $1.99 purchase to remove the ad; there is no subscription. The app is available in 15 languages. If you already use it for the fridge, the setup is covered in the earlier barcode and reminders walkthrough, and the medicine cabinet audit post applies the same method to first-aid kits.

A ten-minute bathroom audit

Take everything out of the cabinet and the makeup bag. For each product: look for a printed date and a jar symbol. If it has a date that has passed, or you are sure it was opened longer ago than its PAO, bin it (and note that empty sunscreen bottles usually recycle; half-full ones usually do not). For everything you keep, add it to the app with your best guess of the opening date; a rough date beats no date, and you will be exact from now on. Finally, buy a fine marker and write the opening month on new products as you open them, as a backup to the phone.

Where this is overkill: a lip balm you finish in a month, a powder you have had for years without issue, a bar of soap. Save the tracking for the products that matter: anything for the eyes, anything with SPF, anything expensive, and anything you only use a few times a year. Those are the ones where the date is the difference between a product that works and one that looks like it does.