Most skincare and hair products have a recommended period of use after opening, but there is no single expiry timeline that applies to every product. The Period After Opening (PAO) symbol, printed expiry date, storage instructions and manufacturer guidance are the best starting points.
The PAO symbol looks like an open cosmetic jar with a number followed by the letter M. For example, 12M means the product is intended to be used within 12 months of opening, while 6M indicates six months.
Check the label of your cleanser, moisturiser, serum, sunscreen, shampoo, conditioner and hair mask. If a product develops an unexpected smell, colour change, separation or texture change, stop using it and consult the manufacturer's guidance. A normal appearance does not guarantee that a product remains safe or effective.
Skincare and Hair Product Expiry: Key Takeaways
- Check the PAO symbol: The number followed by M indicates the intended period of use after opening.
- Check the expiry date too: Do not use the PAO as permission to ignore a stated expiry date.
- Skincare and hair products vary: Formulation, packaging, preservatives and storage conditions affect product stability.
- Watch for unexpected changes: Unusual smells, colour changes, separation and texture changes can indicate deterioration.
- Sunscreen needs extra attention: Follow the printed expiry date and storage instructions rather than relying on appearance alone.
- Store products properly: Keep containers closed, avoid excessive heat and follow the manufacturer's directions.
- Track opening dates: A simple note on the container or in your phone can help you manage your beauty shelf.
1. What Does PAO Mean in Skincare and Hair Care?
PAO stands for Period After Opening. It indicates the period during which a cosmetic product is intended to remain suitable for use after opening, subject to the stated conditions.
You may find the PAO symbol on skincare, hair care and makeup packaging. It is particularly useful for products that you open and use over several weeks or months.
How to Read the PAO Symbol
The letter M stands for months. The number indicates the recommended period of use after opening.
Intended period of use after opening
Intended period of use after opening
Intended period of use after opening
Intended period of use after opening
Intended period of use after opening
Intended period of use after opening
The open-jar symbol may appear on the product container, outer carton or both. If the packaging provides specific instructions, follow them.
The PAO system is used in cosmetic labelling in markets including the European Union. The European Commission's cosmetics framework distinguishes between minimum durability and the period after opening. Read the European Commission's cosmetics legislation for further information.
When Does the PAO Countdown Begin?
For practical purposes, record the date you first open the product and begin using it.
For example, if you open a moisturiser on 1 January and the label says 12M, its recommended post-opening period runs for approximately the following 12 months. Follow the manufacturer's precise expiry and usage instructions if they specify a date.
Pro tip: Write the opening date on the carton or keep it in a simple skincare tracker. This is particularly useful for products you use only occasionally, such as hair masks, exfoliating treatments and specialised serums.
2. PAO vs Expiry Date: What Is the Difference?
PAO and expiry dates are related, but they are not interchangeable. Understanding the difference helps you decide when to review a product and when to replace it.
| Feature | PAO | Expiry or Minimum Durability Date |
|---|---|---|
| What it tells you | The intended period of use after opening | The date or period through which an unopened product is expected to remain suitable under stated conditions |
| When it matters | After the product is opened | Before and after opening, according to the label |
| How it appears | An open-jar symbol with a number and M | A printed date or wording such as expiry or best before |
| What to do | Track when you first open the product | Follow the stated date and manufacturer instructions |
What If the Expiry Date Comes Before the PAO Date?
Do not use the PAO as permission to continue using a product beyond its stated expiry date. Follow the earlier applicable limit and the manufacturer's instructions.
What If the Product Has No PAO Symbol?
Not every cosmetic product uses a PAO symbol. Some products display an expiry or minimum durability date instead, and labelling requirements vary by market.
If neither is clear, check the manufacturer's guidance rather than guessing based on the product category.
Can an Unopened Product Still Expire?
Yes. An unopened product can still deteriorate over time. Ingredients may change, and unsuitable storage conditions can affect stability even when the packaging has not been opened.
The US Food and Drug Administration explains that cosmetic shelf life depends on the product, how it is used and how it is stored. Read the FDA's guide to cosmetic shelf life.
3. How Long Do Skincare Products Last After Opening?
The recommended period varies by formulation, packaging, preservatives and storage. Use the following table as a checklist, not as a substitute for the PAO or expiry date on your actual product.
| Skincare Product | What to Check After Opening | Special Consideration |
|---|---|---|
| Facial cleanser | PAO, smell and consistency | Keep the cap closed and avoid contaminating the opening. |
| Moisturiser | PAO, texture and separation | Use clean hands or a clean applicator. |
| Face serum | PAO, colour and consistency | Follow any light, heat or refrigeration instructions. |
| Vitamin C serum | PAO, colour and storage guidance | Some formulations change colour as they oxidise. Check product-specific guidance. |
| Retinol products | PAO, expiry and storage instructions | Light, air and heat sensitivity vary by formulation. |
| Exfoliating acids | PAO, expiry and product instructions | Do not continue using a product that has changed unexpectedly. |
| Eye cream | PAO and hygiene guidance | Take extra care around the eye area. |
| Face masks | PAO, expiry and consistency | Avoid introducing water or contaminants into the container. |
| Sunscreen | Printed expiry date and storage guidance | Do not rely on appearance alone to judge effectiveness. |
How Long Does Moisturiser Last After Opening?
Start with the PAO symbol on your moisturiser. A jar, tube and airless pump can have different packaging and hygiene characteristics, so do not assume every moisturiser has the same lifespan.
If the product develops an unusual smell, visible separation, a marked colour change or an unexpected texture, stop using it even if the PAO period has not ended.
How Long Does a Vitamin C Serum Last After Opening?
Vitamin C serums vary significantly in formulation and stability. Some formulations are more sensitive to air, light or heat than others.
Follow the manufacturer's storage instructions and watch for unexpected changes in colour, smell or consistency. A colour change can be a warning sign, but its significance depends on the specific formulation.
Do not rely on a generic online timeline to decide whether a particular serum is still suitable.
How Long Does Retinol Last After Opening?
Retinol products also vary by formulation and packaging. Follow the product's PAO, expiry date and storage directions.
If the product is designed to be protected from light or heat, keep it in the recommended environment. Do not assume that every retinol product needs refrigeration or that every product has the same stability.
What About Sunscreen?
Sunscreen deserves particular attention because it is intended to provide a specific level of sun protection.
Follow the printed expiry date and storage instructions. If the product has expired, discard it. If it has changed noticeably in colour or consistency, replace it rather than assuming it still provides the labelled protection.
For more information, read the FDA's sunscreen guidance.
4. How Long Do Hair Products Last After Opening?
Hair products are often used in the shower or stored in humid bathrooms. Moisture, heat and repeated handling can affect product quality, so the PAO and storage instructions matter here too.
| Hair Product | What to Check | Storage Tip |
|---|---|---|
| Shampoo | PAO, expiry and consistency | Close the cap after use. |
| Conditioner | PAO, smell and texture | Keep water from entering the container. |
| Hair mask | PAO and product-specific directions | Use clean, dry hands or a clean applicator. |
| Leave-in conditioner | PAO, smell and texture | Close the bottle or pump securely. |
| Hair serum | PAO, expiry and consistency | Store away from direct sunlight if instructed. |
| Hair oil | PAO and changes in smell or appearance | Keep the cap tightly closed. |
| Styling cream or gel | PAO and consistency | Avoid leaving the container open. |
| Heat protectant | PAO and expiry instructions | Follow the manufacturer's storage guidance. |
| Hair spray | Expiry and packaging instructions | Follow label precautions and storage guidance. |
How Long Does Shampoo Last After Opening?
There is no universal number of months that applies to every shampoo. Check the PAO symbol and any printed expiry date.
If your shampoo develops an unusual smell, unexpected separation or a noticeable change in consistency, stop using it and consult the manufacturer's guidance.
How Long Does Conditioner Last After Opening?
Conditioners have different formulations, so the label is the best guide. Keep the container closed between uses and avoid adding water to stretch the product.
If the product separates unexpectedly, changes smell or texture, or no longer resembles its normal formulation, do not assume it is still suitable simply because some product remains in the bottle.
How Long Does a Hair Mask Last After Opening?
Hair masks are often used less frequently than shampoo or conditioner, which makes it easier to lose track of their opening date.
Write the date on the packaging when you first open the mask. Follow the PAO and storage instructions, and avoid repeatedly dipping wet fingers into the product.
Do Leave-In Conditioners and Hair Serums Expire?
Yes. Leave-in conditioners and hair serums should be used according to their PAO, expiry and storage instructions. Because they remain on the hair, do not continue using a product that has developed an unexpected change in smell, colour or consistency.
5. How to Tell If a Skincare or Hair Product Has Gone Bad
The PAO is useful, but you should also pay attention to changes in the product itself. Cosmetic deterioration may not always be obvious, and a normal appearance does not guarantee that a product is safe or effective.
A product that suddenly separates, develops unusual clumps or becomes difficult to mix may have deteriorated. Some products naturally require shaking, so compare the change with the manufacturer's instructions.
An unexpected change in colour may indicate oxidation or other deterioration. This is especially worth checking in products whose instructions specify a particular appearance or storage condition.
A new rancid, sour or otherwise unusual odour is a reason to stop using the product. Do not try to mask the smell with fragrance or mix the product with another formula.
A broken seal, damaged pump, cracked container or compromised cap can affect product protection and hygiene. Check with the manufacturer if you are unsure whether the product remains suitable.
Stop using the product if it causes a new or unexpected reaction. Seek medical advice if the irritation is severe, persistent or worsening.
The FDA notes that cosmetics can deteriorate through factors such as microbial contamination, changes in preservatives, exposure to heat and sunlight, and repeated contact with fingers or applicators. Read the FDA's cosmetic shelf-life guidance.
Important: Never taste a cosmetic product to test it, and do not assume that a product is safe just because it looks and smells normal. Follow the label and manufacturer guidance.
6. Does Packaging Affect How Long a Product Lasts?
Yes. Packaging can influence how much air, light, moisture and direct contact a product experiences during use.
| Packaging Type | What to Consider |
|---|---|
| Jar | Repeated finger contact can introduce contaminants. |
| Tube | Can limit direct contact with the remaining product. |
| Pump bottle | Can reduce repeated exposure, depending on the design. |
| Dropper bottle | The dropper needs careful handling to avoid contamination. |
| Spray bottle | Avoid contact between the nozzle and skin or other surfaces where possible. |
| Single-use sachet | Follow the instructions and avoid keeping opened contents beyond the intended use. |
No packaging type guarantees a particular shelf life. The formula and the manufacturer's testing and instructions still matter.
Are Airless Pumps Better?
Airless packaging can help limit a product's exposure to air and repeated direct contact, depending on its design. However, it does not make the product immune to deterioration or remove the need to follow the PAO and expiry instructions.
Can You Keep Products in the Bathroom?
You can store products in the bathroom if the label permits it and the environment is suitable. However, repeated exposure to heat, humidity and temperature changes may affect some formulas.
If your bathroom becomes very hot or humid, store sensitive products in a cooler, dry location when the manufacturer recommends it.
7. How to Store Skincare and Hair Products Properly
Good storage habits can help preserve product quality, but they do not extend the official PAO or expiry period.
- Keep products tightly closed. Close lids and caps immediately after use.
- Store away from direct sunlight. This is especially important for products whose labels specify protection from light.
- Avoid excessive heat. Do not leave products in a hot car or beside heat-generating appliances.
- Keep water out of containers. Avoid diluting products or dipping wet fingers into jars.
- Use clean hands or applicators. This helps reduce contamination.
- Follow refrigeration instructions. Refrigerate only when the manufacturer recommends or permits it.
- Keep original packaging when useful. It may contain the expiry date, batch number, instructions and storage details.
- Record the opening date. A small label can help you track products that are used infrequently.
Storage reminder: Do not add water, saliva or other ingredients to a product to restore its texture or make it last longer. Such changes may introduce contaminants or affect the formulation.
8. What About Products That Are Past Their PAO?
If a product has passed its recommended PAO, follow the manufacturer's advice and replace it when instructed. Do not continue using it solely because it looks normal or because the container is not empty.
Pay particular attention to products used around the eyes, products with specific efficacy requirements such as sunscreen, and products that have been stored in unsuitable conditions.
Can Expired Skincare Cause Breakouts?
An expired or deteriorated product may irritate skin or be unsuitable for continued use. However, not every breakout is caused by an expired product.
If a product appears changed or causes a new reaction, stop using it and assess the situation rather than continuing to apply it.
Can Expired Hair Products Damage Your Hair?
A product that has deteriorated may no longer perform as expected and could irritate the scalp. Changes in smell, texture or appearance should not be ignored. Discontinue use and check the manufacturer's guidance.
Should You Use a Product Past Its PAO If It Smells Fine?
No. Smell alone is not a reliable test of product safety or effectiveness. Follow the PAO, expiry date and storage instructions even if the product appears unchanged.
When in doubt, replace it. Do not attempt to rescue a product by mixing it with another formula, adding water or changing its storage conditions after the recommended period has passed.
9. Create a Simple PAO Tracker for Your Beauty Shelf
Keeping track of expiry dates does not need to be complicated. A basic list can help you identify which products to use, review or replace.
| Product | Date Opened | PAO on Label | Review Date |
|---|---|---|---|
| Vitamin C serum | 1 January | 6M | 1 July, subject to expiry instructions |
| Moisturiser | 15 February | 12M | 15 February the following year, subject to expiry instructions |
| Shampoo | 1 March | 12M | 1 March the following year, subject to expiry instructions |
| Hair mask | 10 April | 6M | 10 October, subject to expiry instructions |
These are illustrative examples, not universal recommendations. Use the PAO and expiry details on your actual products.
Your Five-Step PAO Tracking Routine
A simple system helps you manage products without keeping a complicated inventory.
Write the date on the container or record it in your phone.
Check both details rather than relying on the opening date alone.
Follow the manufacturer's directions for temperature, light and handling.
Pay extra attention to products you use infrequently.
Follow the relevant limit and discontinue products that appear to have deteriorated.
This is particularly useful for skincare routines with multiple serums and hair routines with several masks, styling products and treatments.
10. Buy the Right Amount and Use Products More Mindfully
Buying more products does not necessarily create a better routine. If you own several similar serums, moisturisers or hair masks, you may struggle to finish them within their recommended period after opening.
A more practical approach is to:
- Choose products that address a clear skincare or hair care need.
- Avoid opening several similar products at once unless you need them.
- Check the PAO and expiry information before purchasing.
- Follow storage and application instructions.
- Review what you already own before restocking.
Explore the Bodycraft Shop skincare collection, shampoo collection and System Professional collection to find products suited to your routine.
Before purchasing, review each product's current details, directions and packaging information. Choose products you can realistically incorporate into your routine rather than accumulating more products than you need.
A smarter beauty shelf is not about owning more. It is about choosing well, storing products properly and using them within their recommended period.
11. Frequently Asked Questions About PAO and Product Expiry
1. What does 12M mean on skincare products?
12M means the product is intended to be used within 12 months after opening, subject to its expiry date and storage instructions. The symbol usually appears as an open jar with 12M inside or beside it.
2. How do I know when a skincare product expires after opening?
Look for the PAO symbol, printed expiry date and product instructions. Record the date you first open it so you can track the recommended period. If the product changes unexpectedly or causes a reaction, stop using it.
3. Does PAO start from the manufacturing date or opening date?
PAO refers to the period after opening, not the manufacturing date. The product may also have a separate expiry or minimum durability date, which must be considered.
4. How long does shampoo last after opening?
There is no universal duration for every shampoo. Check its PAO symbol, expiry date and storage instructions. Stop using it if it develops an unexpected smell, consistency or appearance.
5. Can I use skincare after the PAO period?
Follow the manufacturer's instructions and replace the product when its recommended period has ended. A normal appearance or smell does not guarantee that the product remains suitable.
6. Does unopened skincare expire?
Yes. Unopened products can still reach their expiry or minimum durability date. Storage conditions also affect product quality, so keep the packaging and follow the manufacturer's guidance.
7. Should I refrigerate my skincare products?
Only if the manufacturer recommends or permits it. Some products have specific storage requirements, while others are intended to be stored at room temperature away from excessive heat and direct sunlight.
8. How long does sunscreen last after opening?
Follow the printed expiry date and the manufacturer's instructions. Do not rely on a general PAO estimate or the product's appearance alone to determine whether it still provides the labelled sun protection.
9. Can I extend the shelf life of skincare by keeping it in the fridge?
Refrigeration does not automatically extend a product's official PAO or expiry period. Store it as directed by the manufacturer and do not assume that colder storage makes an expired product suitable for use.
10. What should I do if my skincare product changes colour?
Check the manufacturer's instructions and stop using the product if the change is unexpected. Some formulas can change appearance for specific reasons, but an unexplained colour change, unusual smell or separation should not be ignored.
Final Verdict: Check the Label Before You Keep Using It
The PAO symbol is one of the simplest ways to manage the shelf life of your skincare and hair care products. It tells you how long a product is intended to remain suitable for use after opening, while the expiry date and storage instructions provide additional guidance.
- Read the label: Check both the PAO and any expiry date.
- Watch for changes: Unexpected colour, smell, texture or separation can be a warning sign.
- Store products properly: Keep them closed, avoid excessive heat and follow the manufacturer's instructions.
A product is not automatically safe just because it looks normal, and an unopened product is not automatically usable forever. When in doubt, check the manufacturer's guidance and replace products that are expired or appear to have deteriorated.
Your skincare and hair care routine works best when the products you use are appropriate, properly stored and within their recommended period of use.
Build a Beauty Routine That Works for You
Explore skincare essentials, shampoos and professional hair care products suited to your routine. Review product details, follow storage instructions and choose products you can use consistently within their recommended period.
Explore Bodycraft Shop →This article provides general information about cosmetic product storage and shelf life. Product stability and suitability vary by formulation, packaging and storage conditions. Always follow the product label and manufacturer's instructions. When a product has expired, deteriorated or causes an unexpected reaction, discontinue use and seek appropriate professional advice if needed.
