Hey! Now that we’ve gotten your attention with our greenwash-y, SEO-friendly title (thanks, Google), you should know that while there’s no such thing as “eco-friendly” bar soap, here’s what to be wise on when you’re shopping so you can pick the best option for you, the planet, and the people making your stuff.
Remember when bar soap was…gross? Well, we’ve come a long way and it seems like bar soap is back in vogue (literally). About 83% of Americans report that they use bar soap and, for the first time in a century, bar soap sales are soaring past liquid options in the UK. If you’re looking to ditch the packaging that liquid soap brings and transition to bar soap, this guide will help you make the wisest choice on your path to bathroom nirvana.
What to Be Wise On:
Opting to wash with a bar of soap instead of liquid soap is already a step in the right direction. Life-cycle assessments show that the carbon footprint of liquid soap is 25% higher than bar soap. That’s because a pump of liquid soap uses a greater mass of soap (almost 7 times more!) than spreading some on with a bar. Plus, you’re ditching all that plastic packaging that requires energy to produce and dispose of. Regardless of which soap you use, be mindful of the ingredients that go into making it and how much water you use while washing with it.
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The Factors To Consider:
Materials
Humanity hasn’t come a long way from the early origins of soap. The ancient Babylonians in 2800 BC used “fats boiled with ashes” as a form of soap, which may sound horrifying, but the modern process isn’t so far off. In 1791, a French chemist patented a soap-making process that combines soda ash from common salt with fats from animals or vegetables. The bar soap we know and use today takes this combination, dries it into pellets, and then mixes it with fragrances and dyes before cutting it into bars.
Fats
Today, many soaps have ditched the animal fat (called tallow) and use plant-based materials instead. In fact, one of the most widely-used substitutes for tallow is palm oil. Like tallow, palm oil is the ingredient that conditions your skin when you’re washing, but palm oil production has some major issues. When produced irresponsibly, palm oil can contribute to deforestation, displace Indigenous peoples, and exploit child labor… which is not so silky smooth. But, before you disown the idea of palm oil, note that some palm oil can support livelihoods in rural farming communities and be produced without contributing to deforestation or ecosystem disruption. Many brands are choosing to source palm oil from more responsible suppliers, so check the label for some helpful certifications (more on that below).
Preservatives
The red flag list doesn’t stop there. Many common bar soaps are made with several potentially risky ingredients that act as both preservatives and antibacterial barriers, but can also cause damage to our bodies and our marine ecosystems. Ethoxylated ingredients, isothiazolinone preservatives, parabens, and triclosan are some pesky ingredients to look out for since they are linked to cancer, cause skin irritation, and have been known to disrupt the endocrine system.
Fragrances
The most elusive ingredient of all might be fragrances. That’s because fragrances are protected from disclosure. While “fragrance” might appear to be one ingredient on the label, that word could potentially comprise hundreds of chemical compounds just for one scent! Always double-check the label to make sure you’re comfortable with what you’re putting on your body.
Certifications
If reading each and every ingredient on a label isn’t your thing (we know, it’s a lot!), then try looking for certifications to cut back on the bad and get more of the good. Certifications are in place to cultivate trust between consumers and brands or products, but this isn’t always the case. Some certifications, at best, give minimal insight into a brand’s environmental impact, and, at worst, can reinforce greenwashing. Sometimes, though, it’s not so black and white.

Leaping Bunny: This is an internationally recognized symbol that guarantees no new animal tests were conducted in the development of a product. PETA’s Cruelty-Free is a similar certification, which denotes if a company does not conduct, commission, pay for, or test on animals. These certifications are important for alleviating your animal welfare concerns.

EWG-Verified™: The Environmental Working Group is a non-profit and their label ensures products are free from the chemicals of concern that are outlined in their unacceptable list.

Roundtable on Sustainable Palm Oil (RSPO): This certification aims to verify that palm oil suppliers are using practices that don’t contribute to deforestation or ecosystem disruption. However, there are some pretty serious concerns about the RSPO’s credibility. In particular, there have been accusations of greenwashing and claims regarding how sufficient the RSPO’s audits of companies are, how slowly they move on instating consequences for members that break rules, how much influence members hold, how low their standards are, how effective they are at curbing deforestation, and how accessible the certification is to smallholder producers.

Fair For Life: This label works to ensure that each player in the supply chain operates with fair pricing, working conditions, and contractual obligations. Fair for Life is part of the fair trade movement and is helpful when assessing many at-risk ingredients like palm oil because it can paint a more complete picture of who was impacted along the supply chain, and how. There are some concerns, though, about the accountability mechanisms in place to hold producers actually accountable.
Water Use
If you’re considering buying a new bar of soap, it’s likely that you’re thinking of using it to wash your hands, face, or body. To lather up, we use water from the sink or shower…and that adds up fast. According to a recent study, 58% of the global population is washing their hands at least 5 times a day after the COVID-19 pandemic. If each person listens to the CDC and washes for 20 seconds each time, they’ll likely use 3.7 gallons of water just washing their hands…every day.
One of the main reasons we’re using so much water is because we leave the faucet on while washing. Turning off the faucet can reduce the environmental footprint of water use because wastewater treatment plants are responsible for 9% and 4% of methane and nitrous oxide emissions globally, respectively. And because water treatment and movement require energy, which is the greatest source of global emissions, taking the extra step to cut back on water use can have significant environmental payoffs.
Besides limiting water waste, we need to discuss those pesky ingredients we mentioned earlier. When these chemicals go down the drain, they can be toxic to the aquatic environments that our wastewater ends up in. Triclosan is resistant to degradation, which leads to bioaccumulation (aka a build-up of chemicals in fish). Since up to 96% of this ingredient is rinsed down the drain, it can disrupt the reproductive processes of aquatic species and is considered a major environmental and public health hazard. Isothiazolinone preservatives are also highly toxic to freshwater and marine organisms (five points to anyone who can say ‘isothiazolinone’ five times fast).
A Few Key Takeaways:
Since we use soap to ward off illness and keep us clean, make sure its ingredients aren’t working against you. Refer to our certifications list to limit the harm that certain materials can cause to your body and the planet. Perhaps most importantly, be mindful of how much water you use while washing up with soap. A big portion of carbon emissions for bar soap comes from the use phase, so that means it’s up to you to make a difference.
Common Questions We Get
“What’s the difference between soap and detergent?”
Remember our little history lesson on the origins of soap? Well, we left out a detail. You see, when the world had shortages of animal fats and vegetable oils that were used to make soap during World War I and World War II, chemists had to leverage other raw materials. These other materials were synthesized into chemicals with similar properties that are today known as detergents. Some products on the market that are labeled ‘soap’ are actually detergents. The big difference between a detergent and a soap is that detergents are made of synthetic ingredients, such as surfactants, while soap’s primary ingredient comes from plant oils or animal fats.
“Is liquid or bar soap more sustainable?”
Research has a very clear winner: bar soap has a carbon footprint that is 25% smaller than liquid soap. Liquid soap requires 5 times more energy to produce and almost 20 times more energy to package than bar soap. Plus, we use about seven times more liquid soap than bar soap per hand wash. Apparently, people tend to use about 30% more heated water while washing with bar soap, so keep that in mind if you want to keep your emissions down.