All About Castile Soap, a Vegan Soap

Its Green Cleaning and Personal Uses and How to Make it

Castile Soap


Castile soap is a vegetable soap traditionally made from 100 percent pure olive oil, water, and lye. It is a vegan product because it does not include the addition of animal fats as some other soaps might. It is believed to have originated from a region in Spain historically called Castile, which is where it takes its name from. Sometimes castile soap is called olive oil soap. Castile soap is available in bar or liquid form. For some great brands to choose from, check out the top Castile soaps for green cleaning.


Several modern formulations have tweaked the time-honored original recipe with the addition of natural ingredients, such as:

  • aloe vera gel (for moisturizing benefits)
  • "butters" (e.g., shea butter)
  • essential oils (e.g., peppermint, lavender)
  • natural antioxidants and preservatives (e.g., rosemary extract, citric acid, Vitamin E)
  • salt (used in bar soaps to make them harder and last longer)
  • vegetable oils (e.g., hemp, coconut, avocado oils, etc.)

True castile soap does not contain harsh synthetic detergents, and the best ones don't add any skin-irritating artificial colorants, fragrances, or preservatives.

Green Cleaning Uses

Did you know that you can use castile soap to clean your house inside and out? Castile soap is indispensable in green cleaning because it acts as a surfactant and helps lift away dirt and cut through grease. You can use Castile soap to clean your whole house from top to bottom!

Because it's eco-friendly and biodegradable, it's also perfect for cleaning outside your home. So, if you need to wash your car or clean your patio furniture, reach for the liquid Castile soap.

Make Your Own Castile Soap

Want to try making your own homemade eco-friendly cleaners with Castile soap? Check out these fantastic green recipes that are easy, fast, and cost-effective:

To make bar soap, sodium hydroxide is used to saponify the oils. For more information, check out these olive oil recipes.

Other Uses

Castile soap has many personal care uses, such as shampoo, shaving cream, body wash, and even toothpaste. Try adding peppermint if you're brave enough to brush your teeth with it! Also, it's ideal for washing your pets.

Shelf Life

Castile soap normally has a shelf life of about three years. Make sure to check the expiration date on the bottle before using. How you store your soap will affect its shelf-life. For example, if liquid soaps are not closed well and kept in a shower, then the possibility of contaminants entering the product increases. So this means the formulation may be compromised, especially if it doesn't contain any preservatives.

Safety and Environmental Notes

All-natural Castile soap is a green product because it is biodegradable, non-toxic, and safe to use for cleaning and personal care applications.


Because it's soap, it's regulated by the Consumer Product Safety Commission (CPSC), not by the FDA. The term "Castile soap" doesn't appear to be regulated in any way, so look out for companies adding in synthetic detergents and using hardly any olive oil at all.