Let me guess – you’ve been rummaging around in one of your make-up bags and come across an old lash serum. Win! You’re going to have fluttery and full lashes in no time.

But wait – it’s already been opened. And like any other skincare or beauty product, you know that lash serum probably has an expiry date. So, how long does lash serum last?

Let’s dive in!

Does Lash Serum Expire?

Bear in mind that most brands are designed to be used for 3 months at a time. To ensure great results, I’d recommend opening it before the 2 years are up.

How Can I Make My Lash Serum Last Longer?

While 6 months might seem like a short shelf life for a beauty product, a bottle usually contains enough product to be used for around 3-4 months at a time. This allows the serum enough time to prolong your lashes’ anagen phase, resulting in fuller lashes that are both longer, conditioned, and generally healthier.

Here’s how you can prolong the life of your lash serum to ensure an effective formula and visible results:

#1 Keep Applications Consistent

You’ve typically only got around 6 months’ worth of use – this means you need to be consistent with your applications if you want to get your money’s worth. Skipping days, or going weeks at a time without using your serum can mean that it ends up expiring before the 3 month use period is up.

Not only does this mean you’ll have wasted both your money and your growth serum, but it also means that your results aren’t going to be as good as they could be. Consistent, daily application is key. 

#2 Store Your Lash Serum in a Cool & Dry Place

Like your other beauty and skincare products, a growth serum is best stored in a cool, dry place away from sunlight. While your lash serum bottle might look pretty on your dressing table, prolonged contact with sunlight can end up damaging the formula.

This is true for all your beauty products: UV rays can literally break down the emulsifiers in cream, oil, and lotion formulas, impacting the efficiency of the product.¹ Storing your trusty bottle in a make-up bag or in your bathroom cabinet is the best way to ensure that it remains functional.

#3 Don’t Overuse Your Serum

Most of them are designed to be applied once a day, preferably before bedtime as part of your nighttime skincare routine. There’s no use in applying your serum twice a day unless the manufacturer recommends doing so.

In fact, applying your serum more than once a day can actually increase your chances of developing side effects, especially if you’re using a lash serum that contains prostaglandins. (Prostaglandins are chemical compounds used in certain eye medications and certain lash serums, and can cause orbital fat loss, discoloration, and irritation.)

You also need to be careful when applying your lash serum – using too much product will both irritate your eyes and also mean that you might not get the full 3 months out of it. If you do use too much by mistake, simply wipe off the excess with a cotton swab and be more precise with your next application.

How Long Do Homemade Lash Serums Last?

Now, what about DIY options? Personally, I prefer a homemade product – they’re safer for the eyes, they’re more affordable, and they can last much longer than your typical shop-bought serum.

So, how long do they last? To keep things simple, I’ve made a list below of all the various natural ingredients you can use, and how long they can last once they’ve been opened.

Coconut Oil

Using coconut oil is a popular homemade trick used to condition and strengthen the lashes. Once opened, refined coconut oil should last for around 18 months, while virgin coconut oil can last for up to five years. Although do make sure that your coconut oil (and any other natural ingredient) isn’t contaminated with other products. Don’t double dip – use an empty serum dispenser to keep things hygienic.

Castor Oil

Castor oil is another popular DIY hack for your lashes – and it’s also incredibly durable! Depending on the quality of the castor oil, it can last between 1 and 5 years when correctly stored.

Vitamin E

Vitamin E is great for your skin and hair, making it great for strengthening the lashes and preventing breakage. Generally, Vitamin E can last for up to 36 months once opened – do note that this applies to 100% pure Vitamin E oil, with nothing extra added.

Essential Oils

Essential oils are a staple in any good DIY formula. You can expect them to last 2 to 5 years when stored away from the sun.

References

1. Niree Noel (2017). How the Sun Damages Beauty Products and Treatments. Retrieved from: https://www.allure.com/story/sun-damage-on-beauty-products-and-treatments (Accessed 22 September 2022)