Article by: Perry Romanowski

I have personal care products that I haven’t opened for a few years.  These are mostly hair styling products that I got for free and have never got around to using.  It takes me a long time to go through a hair styling product.  This experience demonstrates a way that consumers might behave and it suggests that you need to think about it when deciding whether your products are stable enough.

Stability testing

We have previous written about stability testing of cosmetics.  In that article, our advice was that you should shoot for making formulas that last at least a year.  And we stand behind that advice.  Most cosmetic products can not be expected to remain “fresh” for more than a year.

I came across this article that gave expiration dates for cosmetic products.  Here is what they suggest.  While I’m not sure this is what is necessary, this is what at least some consumers will expect.

Less than a year stability

Products that are in small packages (like packets) or have a high level of anti-oxidants in them can not be reasonably expected to be stable for very long.  According to the guidelines being given to consumers, 3 months to a year is all that should be expected for these products.  They say anti-acne products also but that anti-acne products are a monographed OTC which are required to have an expiration date on them.  So products are good up to at least the expiration date.  The following products need around 6 months of stability

  • Eye products – mascara, eye liner
  • Anti-aging products (with antioxidants)

One Year

Most products should be stable for a year when you’re formulating.  Users expect the following products to last about a year.

  • Nail polish
  • Bath oil
  • Sunscreen
  • Anti-dandruff shampoo

More than one year

While most companies will only guarantee that their products will be stable for a year, consumers expect the following products to last longer.  Fortunately, these things are typically used up prior to a year.

  • Hair products – shampoo, conditioner, styling products
  • Shower gel
  • Skin lotion
  • Lipstick
  • Foundation
  • Perfume
  • Shaving cream
  • Bar soap

If you’re formulating cosmetic products it’s helpful to know the expectations of your consumers.  Hopefully, this list will help you in your future formulating efforts.



  1. Avatar

    Interesting site! As a consumer I’ve become more health conscious especially after becoming a mom. I’d rather a product state how long a certain product should last than put more preservatives and stabilizers to extend the use of that particular product…. even if it means I have to throw it out and buy new. I know a man might be a little different but as a woman and a mom, that is how I feel.

    I’ve actually come across your site as I have been studying how to make my own products.

    1. Avatar
      Perry Romanowski

      It’s difficult to say how long a product will last because it is highly dependent on what environment it is exposed to. Some people live in environments with more microbes than others. If you wanted to be super safe, more preservatives are better than less. You don’t realize how dangerous exposure to microbes can be, especially to children. This should be much more concerning to you than the effect of exposure to preservatives and stabilizers.

  2. Avatar

    non sequitor question — in your personal opinion, are hair straighteners that contain formaldehyde safe? (ie, coppola keratin, etc.)

    1. Avatar
      Perry Romanowski

      I think they are safe for the person getting the treatment. For the person giving the treatment, not as much.

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