Bars of solid soap might seem old-fashioned, but it looks like they are staging a comeback.

According to market intelligence firm Kantar, sales of bar soaps have been on the up as people look for more ways to cut single-use plastics out of their homes. Brands are responding in kind, with bathroom brands like Orris and Superbon in France, Aárd in Sweden, the Department of Hygiene in the U.K. and HiBar in the U.S. all launching businesses around the idea of solid, plastic-free personal care products. Meanwhile, other personal care brands like Salt & Stone, Glossier and Drunk Elephant have added luxurious solid soaps — with skin-softening ingredients — to their ranges.

Solid soap gets a glow up

Slippery bars of soap haven’t always had a great reputation. In the past, solid soaps have been associated with dry skin, fusty scents and just generally getting a bit gross and sad as they are left to melt at the side of the shower or sink.

The solid soap brands, therefore, have to work hard to convince customers that their products are going to help them strip back their routines — without stripping their skin and hair.

“With solid shampoo bars, there are still a lot of people who are skeptical about it and thinking ‘can this really work?’,” says Aárd cofounder Pauline Norden. “If you’ve been told for years and years that you need these 20 products, it’s hard to imagine that you could use this one product instead.”

Aárd’s website features a Q&A addressing whether or not solid bars of soap provide a haven for bacteria (no), and if it’s really a good idea to wash your face with soap (it depends on the soap in question). Glossier, meanwhile, has taken the approach of taking something customers are already familiar with — its Body Hero shower gel — and turning it into a bar format that it says will have the same skin-restoring effect. Others such as By Humankind and Hibar focus on the moisturizing qualities of their shampoo bars, avoiding the word “soap” altogether.

Scrubbing out bathroom plastics

But there is one benefit to selling personal care products in a solid format that's an easy sell to consumers — the fact that it cuts unnecessary plastic packaging. The global beauty industry generates an estimated 120 billion units of plastic packaging every year, much of which is used to contain watery formulas like shampoos, conditioners and face washes. By removing the water (which accounts for up to 80% of what’s in the bottle for some brands), brands can instead use paper, cardboard or aluminum packaging to store their products.

Compact soap bars, on the other hand, are lighter and therefore more eco-friendly to transport, and because they’re purchased dry they can be wrapped in recyclable paper or cardboard packaging. They can be more efficient, too: a single multifunctional soap bar that can be used to scrub your hair, body and face negates the need to buy separate products for each part of your body.

Solid soap brands are not the only ones working to cut plastic from our bathrooms. Waken is a mouthwash brand that uses recyclable aluminum bottles, while Leaf Shave makes metal razors with replaceable single blades. Then there’s By Humankind and Last Object, two brands that are working to eliminate bathroom plastic waste wherever it can be found — from toothpaste to cotton swabs.

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