A Definitive Guide to All Types of Perms (2024)

During the ‘80s, tight, springy curls were everywhere, and perms were a regular feature of hair salon menus. In the ’90s, they took a backseat to straighter styles and treatments, but today, perms are back and better than ever. With more curl-creating variations available today than in years past, there’s a type of perm for nearly every imaginable wave or curl and hair type and texture.

Tatiana Dudley, Moroccanoil hair stylist ambassador, says that the modern-day perm, which still relies on chemicals to alter the texture and shape, is milder, less damaging, and comes with less processing time compared to perms from the ’70s and ’80s. “Today’s perms are all about conditioning with new products to help protect the hair’s health.” Even celebrities like Katie Holmes and Emma Stone have been known to achieve bouncy curls and natural looking waves with a perm. Below, find everything you need to know about all types of perms.

How Perms Work

The perm is one of the longest-standing hair treatments that continues to evolve. "A perm is short for permanent," says celebrity stylist Ursula Stephen. "The process permanently waves or curls the hair using chemicals and rods to add life, body, and texture to fine hair. If someone's hair is too straight, flat, limp, or doesn't hold a curl, I may recommend a perm as a styling option."

Color and perm specialist Lisa Estridge adds that for a perm to work its curl-creating magic, the solution must utilize specific chemicals to change the hair's texture and curl pattern from the straightest of straight to curly or wavy by following the shape of the rods or rollers used.

On the days leading up to a perm, it's best to prep the hair as much as possible so it takes well to the service. Estridge has her clients condition their hair for one to two weeks before a perm to get it in optimal health. Dudley recommends using a clarifying shampoo the day before a perm to thoroughly clean the hair. "If there is build-up on the hair, it can prevent the perm solution from taking and result in a less desirable outcome. Just be mindful not to over rub or scratch the scalp, which could result in irritation, burning, and pain during the perm."

Different types of perms use different-sized rods, rollers, and specific chemical-based solutions to achieve the desired effect. No matter the perm type, the steps are relatively the same. Estridge says all perms start with shampooing the hair with a clarifying shampoo. "Then, the perm has to be wrapped with the solution before it is applied to the hair," she continues. "If I'm using a hot perm, the head goes under a heat dryer, but not if it's a cold perm." Then, after the perm is set, it is rinsed out and towel-dried. Finally, she says, a neutralizer is applied for five minutes, the rods are removed, and the hair is rinsed again. From start to finish, the entire perming process can last upwards of two hours, if not longer.

Different Types of Perms

While you may think all types of perms are the same from one to the next, they're not. The curl or wave you want, along with your natural hair type, dictates the perm that will work best. Dudley says spiral perms, body waves, and beach wave perms are trending for straight hair. "They look more like a natural wave or curl, which is why they're popular."

Perms can also be classified as cold or hot, which equates to how the perm solution sets. Dudley explains that cold or alkaline perms don't use heat during processing but rather an alkaline solution that coats the hair after being wrapped around a rod. "Cold perms result in tighter, more defined curls, much like the curly perms of the '70s, '80s, and '90s. They are also better suited for unprocessed medium or coarse hair, adding volume, or creating tighter, more defined curls." On the other hand, Estridge says that hot perms, also called acid perms, rely on heat to activate the perm and can often be used on a softer curl.

Pros and Cons

Transforming pin-straight hair into cascades of natural-looking curls and waves with added volume and fullness has never been easier—and safer—than with a modern perm. But even though perms have gotten better and are safer, they still rely on strong chemicals, like ammonium thioglycolate, to break the hair's bonds and alter its natural shape, which can lead to dryness, some damage, and potentially breakage. "There's also the potential for over-processing the hair at touch-up appointments as well as dry hair that's more prone to breakage," Dudley explains.

Still, a perm will add volume and shave time off your regular haircare routine due to its wash-and-go capabilities, says Dudley. Although all types of perms don't last forever despite their name, on average, you can expect their effects to stick around for three to six months, depending on your hair type, length, perm type, and how you care for your hair.

Unlike hair color, which washes or fades away, a perm doesn't. The effects of a perm grows out as new hair grows in. For the most part, the regrowth transitions into a nice wave.

Hair Type Considerations

Before you go down a rabbit hole trying to figure out which perm is suitable for your hair type, Estridge says to consult a perm specialist to see which one is right for your hair. It's important to consider the hair's texture, length, health, and porosity, as well as the type of curl or wave you are looking to achieve, to find the right perm. Perms are rather tricky to do at home yourself, so this is one hair treatment that's best left to the experts.

Maintaining Your Curls

To maintain the curl's shape, do not wash or wet the hair, apply heat, or brush it for at least 72 hours after it is permed to allow the hair to set. While it's perfectly safe to color and highlight permed hair, Dudley says not to color it for a bit after a perm. It's best to give the hair at least four to six weeks to heal between perming and coloring it.

To keep the hair feeling soft and shiny, wash it with gentle, sulfate-free moisturizing shampoos and conditioners, plus a weekly deep conditioning or oil treatment to help mitigate dry ends. Stephen suggests avoiding heat styling with a perm. She also recommends always using a wide tooth comb on the hair instead of a brush. Finally, Dudley says regular trims for length retention are necessary since curly hair can often hide damage and breakage in the hair.