7 Reasons Why You Absolutely NEED to Try Castile Soap and 16 Genius Ways to Use It

Not all soaps are the same; they may clean all right but they might be leaving behind undesirables. There’s a difference between soap and detergent: loose definitions identify soap as a cleansing agent made from natural products and detergent from synthetics.

There’s a little more to it than that: because true soap is oil-based, when mixed with water, it doesn’t rinse entirely cleanly whereas detergent mixes better (it’s less sensitive to minerals in the water) and will float more easily down the drain along with discarded wash water.(1)

Use of the word “detergent” has changed over the years to mean a cleaning agent used in certain contexts (e.g., laundry, dishwasher) and there are now commercially-available natural “detergents” from plant and mineral sources.

There’s scary stuff in popular cleaners.

Many household and personal care cleansers contain harmful ingredients that have been found to be endocrine disruptors and environmental pollutants, as well as causing skin and respiratory tract irritation. Some common toxic soap and detergent ingredients:(2)

  • Diethanolamine (DEA) – shown to be carcinogenic, affecting the kidneys and liver by the Center for Environmental Health.
  • Dioxane – a synthetic derivative of coconut, found to be carcinogenic.(3)
  • Formaldehyde – an all-around irritant and carcinogen, weakens the immune system and can cause chronic fatigue, headaches, respiratory disorders, and arrhythmia.(4) And it’s great for preserving dead frogs.
  • Parabens (e.g., methylparaben, propylparaben) – endocrine disruptors, increasing risk of cancer—especially breast cancer in women.(5)
  • Sodium Laurel Sulfate (SLS) – one of the most common soap and detergent additives, designed to generate lather. It has carcinogenic nitrates, can cause skin irritation, diarrhea, breathing difficulty, and severe eye damage—even blindness. It’s readily absorbed by the skin and can affect organ function.(6, 7)
  • Triclosan – banned in Canada as an environmental toxin and currently under review by the U.S. Environmental Protection Agency, this chemical has been added as an antibacterial. It is a hormone disruptor and may be a contributing factor to antibiotic resistance.

A true soap.

Castile soap is a true soap, traditionally made from plant oils, water, and lye (you can also find lye-free soap). It is called “castile” after the region in Spain from which it originated. The benefits and uses of castile soap are many and can replace many potentially toxic cleaners in your home. Here are some reasons why castile is a very desirable alternative:

  • Doesn’t contribute to antibiotic resistance – when washing, most dirt and germs are caught up in the oils in the soap and removed from the skin (or other surface), then rinsed away. You don’t need to kill them with a chemical, forcing them to find another way to get you.
  • Lathers easily – if the castile soap contains potassium hydroxide (“potash”—not all soaps include it), this compound will saponify the oils to release their cleansing potential and lather. It won’t be a huge, thick lather like chemically-laden cleaners but will bubble quite nicely.
  • Non-toxic and natural – you can eat it (unless it contains lye, which is caustic and can burn the skin—you might get a stomach ache, but it won’t cause cancer or reproductive harm).
  • Environmentally friendly – biodegradable; no poison in, no poison out.
  • Safe for babies and pets – castile is gentle and mild, non-irritating, and natural. Unscented varieties are best for little ones and furry ones—some essential oils are toxic to animals.
  • Vegan and Fair Trade – traditional castile soaps contain no animal ingredients. Companies that manufacture it are often globally conscious and engage in Fair Trade practices. Many soaps are also organic.
  • Versatile – castile soap can be used whenever a cleaning agent is needed—plus some ways you may not have thought of—as a pesticide or treatment for eczema.

16 innovative ways to use castile soap.

1. Bubble Bath – castile soap with your choice of essential oil(s) and glycerin will clean your skin and leave it silky soft. You can make it either invigorating or relaxing, depending on the oil you use.


  • ½ cup warm distilled water
  • ½ cup liquid castile soap, scent of your choice
  • ¼ cup vegetable glycerin
  • Essential oils of your choice (optional)


Mix all ingredients in a jar until glycerin has dissolved—don’t shake too hard or it will become very foamy and you’ll have to wait before using. Some glycerin may settle at the bottom—that’s okay. Once blended, pour in as much as you like under running bath water for the desired amount of bubbles.

2. Body Wash – nourish your entire body with a mixture of castile soap, honey, and the essential oil of your choice.


  • 1/3 cup castile soap
  • 1/3 cup raw honey
  • 1/3 cup olive, jojoba, refined avocado, or almond oil
  • 30-60 drops essential oil (orange, vanilla, lavender, etc., optional—the honey adds its own warm, sweet scent)


Add all ingredients in a bowl and mix until thoroughly combined. Pour into a squeeze-top or pump-top container. Shake well before using.

3. Hair and Make-up Brush Cleaner – many people don’t regularly wash their hair and make-up brushes. Accumulated dirt and skin can accumulate in your brushes, collecting germs and clogging pores. Soak and wash your brushes weekly in castile soap and water.

4. Dish soap – you may use straight liquid castile soap or mix with solid castile soap, water, washing soda, and optional essential oil for clean, germ-free dishware. The washing soda adds a mild abrasive.


  • 1 1/4 cups boiling water
  • 1/4 cup castile bar soap, grated and tightly packed
  • 1 tablespoon washing soda (use a little more for a thicker soap)
  • 1/4 cup liquid castile soap
  • 10-30 drops essential oils (optional – suggestion: 20 drops orange or lemon and 10 drops tea tree)


  1. Add grated castile soap to boiling water and stir until dissolved.
  2. Add washing soda and stir.
  3. Add liquid castile soap and stir.
  4. Let mixture cool, then add essential oils.
  5. Transfer to soap dispenser and replace that store-bought stuff.


  • Soap mixture will harden as it sets. If it’s too thick to pour, just add a tiny bit of warm water and give it a good shake to loosen it up.
  • The amount of washing soda you use will dictate how thick the soap gets, so adjust accordingly.

5. Dishwasher Soap – making your own, you know and can pronounce exactly what’s in it—without bleach, phosphates, or artificial colors and fragrance—and your child won’t have to go to the hospital for eating a pod of it.(8, 9) Like the window washing recipe below, following the soap wash with a vinegar rinse aid will ensure clean, grease-free dishes.


  • 2 cups castile soap
  • ½ cup water
  • 3 drops essential oil (e.g., tea tree)
  • White vinegar for rinse aid


  1. Mix the first three ingredients in a bottle and shake well. (Shake each time before using.)
  2. Use 2 tablespoons per load.
  3. Fill rinse aid compartment with vinegar.
  4. Run the dishwasher as you normally would.

6. Dog Shampoo – gentle and thorough, this pet wash won’t strip the oils from the skin and will leave fur soft and smelling good. Oatmeal contains healthy fats to moisturize Spot’s skin and coconut oil is non-toxic, nourishing, cleansing, and moisturizing. Add a drop each of orange and lemon oils to keep bugs away.


  • ¼ cup colloidal oatmeal (i.e., ground to a powder)
  • 1 cup unscented or hemp tea tree castile soap
  • 2 tablespoons coconut oil, melted
  • ¼ cup warm water


  1. Grind oatmeal and set aside.
  2. Mix castile soap and coconut oil. Add warm water and mix.
  3. Add oatmeal and whisk to break up any chunks.
  4. When bathing, pour the shampoo over your dog’s coat, lather, massage into skin, let it sit for 1-2 minutes (or as long as s/he’ll allow), and rinse.

7. Face Wash – because of its natural mild ingredients, castile can be used on even sensitive skin. Sage is an antibacterial astringent. Blended with chamomile and lavender oil, you get a soothing balm.


  • 1 cup castile soap
  • ½ cup brewed chamomile tea (use 2 teabags)
  • 6 drops sage essential oil
  • 4 drops lavender tea tree oil


Mix all ingredients together and store in a glass jar or plastic tube. Gently clean pores and nourish with anti-inflammatory astringents. Great for acne-prone skin.

8. Floor Cleaner – use on hard floors like tile and hardwood. Only half a teaspoon of castile soap to a bucket of warm water will clean your floor and no rinsing required!

9. Foaming Hand Wash – right out of the bottle, liquid castile is a lathering soap. You can add water to make it go further or a couple of drops of the essential oil of your liking for fragrance and antibacterial properties, like almond, orange, or peppermint.


  • 12 ounces water (distilled or boiled is best)
  • 2 tablespoons liquid castile soap
  • ½ teaspoon liquid oil (e.g., olive or almond, optional)
  • Essential oil(s) of choice for scent (optional)


  1. Fill a soap dispenser with water to about 1 inch from the top.
  2. Add castile soap (NOTE: do not put the soap in first or it will bubble when the water is added).
  3. Add the fruit oil (optional – it helps preserve the life of the dispenser) and essential oils, if desired.
  4. Close and lightly swish to mix. Use as you would any regular foaming soap.

10. Coconut Milk Shampoo – mixed with castile soap, coconut milk nourishes your hair and scalp, leaving it soft. Follow with an apple cider vinegar rinse to condition and naturally smoothe your hair. Simply mix 1 teaspoon coconut milk and 1 tablespoon castile soap in a small jar. If you want to make a larger batch, refrigerate the unused portion between uses.

11. All-purpose Household Cleaner – in a spray bottle, mix 1 cup water with 1 tablespoon castile soap and 10 drops of tea tree, peppermint, pine, or eucalyptus oil for cleaning and disinfecting virtually everything in your home.

12. Laundry Detergent – four ingredients and no toxins: castile soap, borax, washing soda, and optional essential oil will get your clothes clean, rid them of germs, make them smell fresh, and save you a boatload of money.


  • 1 cup borax (a mineral)
  • 1 cup washing soda
  • 1 cup castile soap, scented or not
  • 10-15 drops essential oil (optional)
  • 17 cups of water


  1. In a large saucepan, bring 6 cups of water to a slight boil. Once the water begins to boil, turn off the burner and add the borax and washing soda. Stir to dissolve.
  2. Combine the remaining 11 cups of room-temperature water and castile soap in a 2-gallon bucket. Add essential oil if desired.
  3. Pour the hot borax mixture into the bucket and stir.
  4. Pour the entire mixture into a storage container, preferably glass.
  5. As the soap sits, the mixture will form into a gel. There may be liquid and gel separation—stir or shake to remix. Use 1/8-1/4 cup of soap per load of laundry. For stains, use a small amount of soap directly on the stain and rub gently. The gel will dissolve in the water of the washing machine.

13. Shaving Cream – commercial shaving creams contain harsh and sometimes toxic chemicals that can irritate skin.(10) Mix castile soap with raw honey and olive or avocado oil for a close, moisturizing, nutritious shave that won’t clog the razor.


  • ½ cup oil (olive, grape seed, avocado, almond, etc.)
  • ¼ cup raw honey
  • ¼ cup liquid castile soap
  • 10 drops of essential oil (optional)


  1. Combine all ingredients in a bowl and rapidly whisk for several minutes until fully emulsified.
  2. Transfer to a pump or squeeze bottle.
  3. Use sparingly—a little goes a long way.

14. Toilet Cleaner – scrubbing bubbles, antibacterial, mildly abrasive, and fresh-smelling…yup, this is the right stuff.


  • ¼ cup liquid castile soap
  • 1 ¾ cups water
  • 2 tablespoons baking soda
  • 8-10 drops of essential oil (eucalyptus, lemon, orange, peppermint, or tea tree)


Mix all ingredients in a 16-ounce or larger squirt bottle, gently shake to mix, squirt, brush, done.

15. Toothpaste – there are a whole host of reasons for making your own teeth cleaner (toxicity of fluoride, other dangerous chemicals, and expense, to name a few). Using melted coconut oil, xylitol or stevia for sweetening, and the essential oil of your choice will deliver whitening, antibacterial, and antioxidant powerhouses to your mouth.


  • 2 tablespoons boiled water
  • ½ cup coconut oil, melted, at room temperature
  • 4 teaspoons castile soap (peppermint or unscented)
  • 1-2 teaspoons xylitol (from birch, to avoid genetically-modified corn) or stevia
  • 30 drops peppermint, spearmint, or anise oil


  1. In a small saucepan, boil a ¼-½ cup of water (it doesn’t have to be exact). Put 2 tablespoons of the boiled water into a food processor or blender. Add all the other ingredients to the blender and whip until frothy—it takes only a few seconds.
  2. Place in a squeezable tube and use just like toothpaste.

16. Window Cleaner – for outdoor windows (or inside if they’re really gunked up), mix 2-3 tablespoons castile soap with 16 ounces of water in a spray bottle, spray and wipe. Follow with a white vinegar wash for grime- and streak-free windows. Don’t mix the vinegar directly with the soap; because vinegar is an acid and castile is alkaline, the acid will separate the oils in the soap and smear whatever you were cleaning. Use the soap first and the vinegar after.

You can make castile soap at home—click here for a recipe and instructions.