One of the most enjoyable parts of vaping is trying out the plethora of e-liquid flavors available. With so many liquids to choose from, it’s easy to accumulate juice a lot faster than you're actually vaping it. In theory, it's not impossible to amass dozens, even hundreds of vape flavors that will wind up laying around and accumulating dust if you’re not careful. 

We're frequently asked how long e-liquids last. Do they expire? Does the flavor degrade over time? What happens after liquids have been on the shelf for a long time? In this article, we’ll look at the effects of time on e-liquid (for the most part they're not good), and also discuss ways to fight the aging process.

However, no matter how long the bottle or this article says you should be able to use an e-liquid, if something tastes off about it, consider throwing it out and getting a new bottle. If the liquid is relatively new, you might consider the manufacturer or the retailer that you got it from.

How Long are Liquids Safe?  

The simple answer is that there's no fixed shelf life for e-liquid. Some bottles have an expiration date, but most don’t. Absent an expiry date, figure your bottles are best used within six months to a year of purchase, two years at the most if they're well cared for.

This life cycle is highly dependent on multiple factors, most of which are related to the method of storage and temperature. The warmer the conditions, the faster the liquid's nicotine will oxidize. Oxidation is a chemical process where molecules break down over time due to conditions like heat. It’s similar to the way that soda goes flat. When you have a carbonated soda and you leave it in the heat, the carbonation goes away due to a breakdown of the carbonated molecules. With nicotine, oxidation leads to darker liquid color and a rougher throat hit once you eventually do go to vape it.

The best way to preserve liquid is to keep it in a cool, dark place. This might be a refrigerator or even a freezer if you're attempting to preserve your liquid for a long time, but the back of a cupboard could be a good storage spot if your house doesn't get too hot in the summer.

Aside from heat and light, air is your liquid's biggest enemy. Constant contact with oxygen will speed the oxidation process - if you're buying giant bottles of your favorite flavor to save money, it might not be a bad idea to get some smaller bottles that each hold a few days' worth of juice so you're not continually exposing the larger supply to air every time you need a tank top-up.

Signs Liquid Going Bad

There are a few warning signs that your liquid could be going bad. The first is color: if your juice is noticeably darker, that's a sign of oxidation. Separation of the various flavor and base compounds could also be a sign of age: if your bottle looks cloudy or the liquid at the top is a different color from the bottom, give it a shake. If the appearance doesn't immediately return to uniform, that's also a bad sign.

Additionally, if the smell is off, then it’s a pretty good indication that it’s going to taste bad, and the liquid is reaching the end of its life. That brings us to our most obvious tell for bad liquids, taste. Most flavors will lose their potency over time, making for a weakly-flavored cloud. Liquids that have been exposed to too much heat and/or light will cause the sugars in VG to condense, leading to a sickly sweet, thick juice that will quickly clog your with carbon buildup.

Takeaway 

Properly stored e-liquids can last a long time, from a year or more to indefinitely. To prolong your liquid's life, keep it in a cool dark place, securely sealed with as little exposure to air as possible. Break big bottles down into smaller ones to reduce the amount of contact between air and liquid and the number of times a bottle is opened before it's emptied.

While we haven't heard reports of anyone being harmed from exposure to expired e-liquids, there's no reason to chance it and you're not going to enjoy vaping them anyway. If your liquid looks, smells, or tastes off in any way, you're probably better off replacing it.