It’s happened to the best of us. One minute you’re spring cleaning happily, and the next, you’re unearthing box after box of forgotten hair dye. It seems a shame to throw it all away, especially when you’d love a style change to go along with that cleaning. The materials are right here in front of you, but is this dye still good to use? Does hair dye expire?

If you’re searching for an expiration date on the packaging, you probably won’t find your answer. According to Sally Beauty, most hair dye manufacturers do not print a date of freshness or a use-by date on their dye products. This is due to the belief that if the package is correctly stored, it has an almost unlimited shelf-life.

In fact, there are no current laws in the US requiring cosmetics manufacturers to include this date on their packaging. However, manufacturers still have the responsibility to test their product extensively and make sure it has a stable shelf life.

Some manufacturers will provide you with the production date of your dye if you call and tell them the batch number printed on their product. This can help you decide whether or not you want to use the dye.

How Long Does Hair Dye Really Last?

With proper storage, the general consensus is that opened hair dye can last from 1-2 years, while a sealed box can last up to 3 years or possibly longer. Proper storage in this case refers to the climate the dye is kept in. The ideal climate for hair dye is in a cool, dark space that has very little exposure to moisture or humidity.

Environmental factors have a lot to do with how fast your hair dye can expire. For instance, keeping the dye in direct sunlight or another warm area can spark unwanted chemical reactions. Heat will cause most hair dyes to separate, causing them to go bad much more quickly.

Leaving the bottles open or exposed to water can cause oxidation, rendering the dye completely useless. You also have the potential for introducing reaction-causing bacteria if the bottles are not sealed tight.

Keep in mind that the brand and ingredients can also contribute to the varying shelf life of hair dye. Professional brands such as L’Oréal and Redken will last longer than drug store and organic brands (organic brands expire faster due to minimal chemical processing).

It is also important to note that these timelines only apply to unmixed chemicals. If you mix the chemicals together and have some leftover after applying to your hair, you must throw this mixture away. The chemical reactions have already started here and are potentially dangerous to your hair if you save the mixture for future use.

Likewise, any hair dye stored in imperfect conditions may go bad much sooner. While a properly-stored dye should stay usable for quite a while, one exposed to extreme heat, air, and moisture might deteriorate in just a few months.

Signs of Expired Hair Dye

So let’s say that you don’t remember if it’s been 1 or 2 years since you purchased that hair dye. We get it, the days are all blurring together at this point. No judgment here. But if you find yourself in this situation, what you can do is examine the packaging and materials inside to determine if they are safe to use.

Package Damage

Package damage and swelling is one of the most visible signs of expired hair dye. If the dye is in a hard box container, it can appear dented, indicating that the materials inside might be compromised. There may even be wet spots on the box where it has come into previous contact with water or chemicals have leaked out into the packaging. The bottle of dye itself may look lumpy or completely swollen as a result of oxidation.

Leaking Fluid

Another visible sign of expiration is when upon opening, a clear, watery fluid comes out of the bottle. There may also be a red, yellow, or orange circle around the cap, or streaks of the same colors in the actual dye. If your intended hair color is not red, yellow, or orange, this coloring can indicate that the chemicals inside have gone bad and are no longer useable. If the dye appears to be murky, has separated into pieces, or looks like it needs to be shaken in order to use, it’s expired.

Separation

It’s also possible for the liquid dye to have expired without a leak in the container. To check for separation, open the bottle carefully without tilting it. Then, slowly tilt the bottle as if to pour it. If one homogenous liquid comes out, you’ve got nothing to worry about, but if a thin, slightly milky but mostly transparent fluid pours out, your dye has most likely separated and gone bad.

Bad Odor

You can also smell the dye by wafting the container under your nose (you don’t want to inhale too much of the scent). Hair dye doesn’t usually have the greatest of smells, but it shouldn’t smell excessively foul or metallic.

Color Test

Finally, if these tests fail you, you can determine if hair dye is expired or not by mixing a small amount in a bowl. Mix it according to instructions and observe the color. Hair dye typically appears lighter than the end-result color, allowing the chemical reactions to take place on your hair, dyeing it. If the hair dye immediately appears to be the end-result color when mixed, the dye is expired and should be thrown away.

home hair coloring set with bowl and brush

The Effects of Expired Hair Dye

If your hair dye has failed one or more of the tests above, or even if you are just unsure about it, it should be thrown away. Expired hair dye can potentially cause significant damage to your hair when used.

The most commonly reported side effect of expired hair dye is ending up with the wrong color. Typically, expired hair dye will turn your hair bright green, but there is the possibility of turning your hair any number of undesirable colors. It may even appear to be dyeing your hair the right color, but actually end up turning out uneven once the color has set.

On the other hand, you may achieve the desired color, but it fades away quickly. Expired hair dye does not last as long as fresh dye. There is even the possibility of nothing happening to your hair. There’s no way to predict the outcome, and you take the risk each time you use expired dye.

The more severe outcomes of using expired dye include damaging your hair so badly it frizzes and/or breaks off. This is usually more visible after the first wash and can require anything from intensive reparation efforts to having your hair cut off in order to fix it. You also run the risk of chemically burning your scalp, losing your hair during the dyeing process, or, less commonly, suffering an allergic reaction due to the expired dye.

Takeaways

When properly stored, open bottles of hair dye have the potential to last for several years, with sealed boxes lasting even longer. However, hair dye can, and does, expire. Several factors influence exactly how long the dye can last, so it is important to evaluate your specific situation when considering using old hair dye.

If you suspect that your hair dye may have seen fresher days, it’s usually better to err on the side of safety and throw it out. Expired hair dye can cause a number of problems that could potentially cost more to fix than simply buying a new bottle.

So, if you’re planning on saving opened hair dye or stocking up on boxes during a sale, remember to store it correctly in order to get the maximum shelf life out of it and reduce your chances of encountering expired dye.