8 Household Uses for Castile Soap—the Natural, Non-Toxic Way to Clean Almost Anything

So often, it’s the simplest things that stand the test of time. Castile soap, an organic and versatile cleaner formulated with vegetable fats, is the perfect example.

Even with its minimalist formula, this powerful household cleaner can tackle tough grime on floors and surfaces, cut through greasy dishes like a champ, and offer load after load of soft, fresh laundry. Best of all, it’s easy to use and cost-effective—and there’s no doubt you’ll figure out a way to use every last drop from the bottle. 

What Is Castile Soap?

Castile soap is a natural, biodegradable, and completely vegan cleaning agent that’s formulated with plant-based oils. It’s never made with animal products nor synthetic ingredients. 

"This soap is named for the Castile region of Spain, which is where it was originally produced," says cleaning professional Robin Murphy, founder of ChirpChirp, a home cleaning company. "It's a gentle and effective soap for lifting dirt, and I think it’s great for cleaning dishes, mopping floors, and laundry—including hand washing delicates."

Similar to other products, each brand puts its own spin on castile soap. Common ingredients include olive, coconut oil, sunflower, and/or jojoba oils, and other botanical fats, says Vanessa Garcia, a professional cleaner with TaskRabbit.

Potassium hydroxide is also typically added to the formula, but its chemical makeup shifts after saponifying the oils into soap and glycerin. Some brands also incorporate essential oils for added scent. 

Common Household Uses for Castile Soap

You can use castile soap throughout your home many different ways. We recommend testing a small, discreet area prior to full usage to ensure it won’t disrupt colors or textures. 

Carpet Cleaner 

Castile soap is a great, cost-effective carpet cleaner that breaks down even tough stains without costing a fortune. Kathy Cohoon, a cleaning professional with Two Maids, says to add a few drops into about 3 cups of hot water. You can also add 1/4 cup of hydrogen peroxide for tougher stains. "Apply it to the area, scrub in circular motions, repeat if needed, and then allow it to dry," Cohoon says. 

Hand Washing Dishes 

Given its mild formula that can still cut through grease and grime, castile soap makes for an excellent dish washing soap. "What I'm washing my dishes with will eventually go into my body, so I prefer this option since it's also more natural and less chemically laden," says Garcia, who says you can use it straight from the bottle, or diluted up to 50 percent with water. Make sure to rinse well. 

Dish Washing Detergent 

Similarly, you can use castile soap in your dish washing machine. However, it needs to be diluted. To DIY your own detergent, combine 8 ounces of castile soap with a cup of water and 3 tablespoons of either vinegar or lemon juice in a well-sealed container. Mix thoroughly and then dispense 1 tablespoon into the detergent compartment. Shake the mixture together before each usage to ensure it’s well mixed. 

Hard Floor Cleaner 

Castile soap is safe for sealed, non-porous hard flooring. "A little goes a long way," Cohoon says. "Simply mix a teaspoon of castile soap into a bucket of warm water and add essential oils if you’d like. Mop and dry as usual." She notes that too much castile soap added to your mixture can leave residue and streaks behind, so be conservative. 

Countertops 

When it comes to keeping your countertops clean, castile soap acts as a gentle alternative to harsh or abrasive cleaners, says Marla Mock, president of Molly Maid, a Neighborly company. "We recommend using it with a little warm water and a gentle cloth, like a microfiber towel," she says. "Our recommended ratio is 1/4 cup of castile soap to a bucket of hot water." 

Bathroom Surfaces 

A mixture of castile soap and water can effectively clean your entire bathroom, including your toilet bowl, bathtub, and vanity sinks. 

"Castile soap offers a hardworking, but not chemical-laden, scrub or spray for bathrooms that is fresh and will keep things clean in the dirtiest room of the house," Cohoon says. "Make a multi-purpose spray or mix it up in a bucket to apply to the area and wipe with a microfiber cloth and dry well." 

Just note that castile soap won’t kill bacteria or viruses like some other cleaners. When you need to deep clean the bathroom, you may want to use a more potent formula. 

Washing Your Walls 

Washing your walls is a great way to keep your home feeling and smelling fresh and clean. Combine 1/8 cup castile soap to a 2-gallon bucket of hot water. Dip a sponge mop with a long handle into the mixture, squeeze out excess water, then rub it up and down your walls. If you notice any residue, you can repeat with just hot water. 

Laundry Detergent 

Using castile soap for laundry is a good, natural alternative to traditional detergent that will still leave your laundry clean. It’s ideal for those with sensitive skin or sensitivities to harsh detergents or smells. "We recommend using it just like detergent or to pretreat stains," Mock says. "Our recommended ratio is 1/6 cup of castile soap added to the washing machine’s water directly."

What Not to Clean With Castile Soap 

Despite the many castile soap uses around the house, it’s important to avoid using this type of cleanser on certain surfaces. 

"I personally have had a hard time using it to clean glass because it’s hard to get the correct dilution so it cleans effectively, without leaving a residue," says Murphy. "It also shouldn’t be used on porous stone—such as marble or limestone—cast iron, or unsealed wood floors." If using it on stainless steel, it’s important to rinse afterward to avoid streaks and residue.