Does shampoo expire? Here's what you need to know

Have you ever thought, does shampoo expire?

Does shampoo expire: Illustration to depict woman shampooing hair
(Image credit: Getty / CSA Images)

So, does shampoo expire? The short answer is yes. We diligently check expiration dates on our food but likely never question the expiration dates of our health and beauty products, such as shampoo. It may never cross your mind, as shampoo seems like one of those products you can rely on having an eternal shelf-life. Well, that sadly isn’t the case. Even the best shampoo bars have an expiry date. 

Your shampoo habits

You are not alone if you have never worried about your shampoo’s expiration date. Since shampoo is used with such high frequency, most of us finish our bottles well before the expiration date. Still, it’s best to keep an eye on the signs that your shampoo is past its prime. With the introduction of more natural, organic options with a much shorter shelf life, get into the habit of checking your expiration dates, and minding your storage habits to keep your bottles fresh. Here’s everything you need to know to keep your shower and your hair safer. 

Shampoo’s expiration date

While manufacturers of personal care products aren’t legally obligated to label their product with an expiration date, you will more than likely come across a code on the back of your favorite shampoo bottle. This code will be a number, most commonly 12 or 24, followed by a capital M. The letter stands for months, and the number represents the allotment of months the shampoo is designed to work properly. The time starts after you open the bottle, meaning you'll have to keep track of the expiration date yourself. That said, if you're able to make a bottle of shampoo last over a year, there is a high possibility that it has expired.  

Shampoo ingredients 

A shampoo’s expiration date depends on its ingredients. While this will vary depending on brands and formulas, you can expect that everyday, popular shampoos often contain:

- sodium lauryl sulfate
- sodium laureth sulfate
- dimethicone
- panthenol
- citric acid
- parabens
- cocamidopropyl betaine

These ingredients do various things: they are cleaning agents, foaming agents and help extend the shelf life, for example. Their quantity levels vary depending on the benefits your shampoo claims to have. These can range from preventing dandruff, eliminating split ends, protecting from frizz, and general hair repair. When you open your bottle, you expose these ingredients to oxygen, which can slowly diminish their abilities. Oxygen can also allow a slow growth of bacteria, reacting with your shampoo’s ingredients. 

The meaning of the expiration date

The expiration date indicates when a shampoo is no longer effective based on the benefits it claims to have. Potential dangers or health risks are minimal, but if you’re paying premium retail for your hair care, you'll want to use it before it’s no longer worth the price tag. Your shampoo should smell as delectable and luxurious as it did on the day you bought it. 

What to look for

If you’re not keen on memorizing the exact time you open each bottle of shampoo you use, there are some easy signs you can look out for to keep expired products off your shelf. You might want to consider throwing away your bottle if it:

- has an odd odor. You should be able to tell right away if your shampoo doesn’t smell fresh. It could even take on a rancid scent.
- looks lumpy. If the consistency is off, or if it’s lumpy or extremely watery, your shampoo is likely expired.
- is a strange color. Conditioner tends to be cloudy, not shampoo
- doesn’t create suds like it used to or leaves residue instead of rinsing off clean.

Make the most of your shampoo

When you’re lathering up, make sure you close the lid and place it in an area where it won’t be exposed to direct sunlight. Sunlight and heat will accelerate expiration, as cosmetics tend to be sensitive to their environment. Ideally, you will want to store your shampoo in a cool and dark environment. It’s also best to ensure the product isn’t getting unnecessarily wet and the bottle isn’t damaged. If your shampoo’s pump or dispenser has become damaged, causing you to open the top for every use, it will probably expire more quickly. It’s also worth noting that natural, organic shampoos may not last as long as traditional shampoos, as they are free from preservatives.