How long should your cosmetic formulas last?
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.
