Bar soap vs liquid: Which is better for the environment?

One Change: Packaging and production adds hugely to environmental costs of liquid soap

“Mr Bloom raised a cake to his nostrils. Sweet lemony wax. - I’ll take this one, he said.”

A bar of lemon soap, bought at Sweny’s Chemists in Dublin, is kept in the pocket of Leopold Bloom as he wanders around the city in James Joyce’s Ulysses. In those days – June 1904, to be exact – talk of 20-second handwashing and antibacterial gels was a long way off, and the Spanish Flu had yet to make an appearance.

These days, most of us won't leave the house without a miniature bottle of sanitiser and a mask – we've never had to think so much about cleaning and disinfecting and handwashing. And in this strange new reality, scientific diagrams have become a sensation – such as the one that went viral for demonstrating how soap can break through the membrane of Covid ("like a nail popping a tyre" according to Unesco), leaving the virus deflated and powerless. Meanwhile, the constant messaging to "wash your hands" has given soap a starring role in the fight against coronavirus.

Soap and water

Yes, the simple, old-fashioned recipe of "a bit of soap and water" has a lot to love. But is a bar of soap any better than a liquid one? When it comes to cleanliness, both are equally effective at killing germs. (And we don't need to worry about bacteria hiding in bars of soap – according to a study published by the National Library of Medicine, and others, a bar of soap cannot transmit infection, so long as you properly wash your hands after touching it, of course.)


When it comes to the environment, there are obvious benefits to opting for a bar of soap – such as packaging. Those big plastic bottles and pumps for liquid soap are exactly the type of waste that is avoidable, unnecessary and makes for heavier transport – ie a bigger carbon footprint. A bar of soap, on the other hand, can be bought with a small wrapper or sometimes entirely without packaging. It can last longer too, with one study finding that we're likely to use about six times more liquid soap every time we wash our hands.

Humble bar

While some brands, such as Ecover, have refillable options, it’s not just packaging that’s an issue with liquid soap. The production of liquid soap requires five times more energy for raw material and almost 20 times more energy for packaging production than a bar of soap. So overall, the humble bar of soap wins out when it comes to being environmentally friendly – and you can support some great Irish, eco-friendly companies too such as The Handmade Soap Company, which also has a range of liquid soaps in recycled packaging, the Donegal Natural Soap Company, and the Palm Free, Zero Waste Irish Soap.