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Castile Soap

Castile Soap

A key part of your DIY cleaning arsenal.Castile Soap forms the base of so many of the products you’ll make, from sprays and dish liquid to hand wash and body wash. Anywhere that needs a clean, from your dishes to your bum, this simple concentrated soap is usually where you start.

Regular price $12.00
Regular price Sale price $12.00
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*Refills arrive in a home compostable Earth Bag. The jar comes full, buy it once and refill from then on.

Quantity

Soap and detergent are not the same thing! However they both work as surfactants to trap and lift dirt so so it can be rinsed away. A pure soap is your most simplest, natural and safest surfactant as well as the most eco-friendly.

What is it & does


Castile Soap is a true liquid soap made from plant oils, rather than a synthetic detergent blend.

Oils are combined with potassium hydroxide through a process called saponification. During this reaction, the oils and alkali are converted into soap and naturally occurring glycerine. The potassium hydroxide is consumed in the process, so no lye remains in the finished soap.

Our formula uses 80% olive oil and 20% coconut oil in the oil base. Olive oil creates the mild, conditioning character Castile Soap is known for, while coconut oil contributes extra cleansing and lather.

Its real cleaning job is as a surfactant.

One end of a soap molecule is attracted to oils and grease while the other is attracted to water. The soap surrounds oily dirt, suspends it in the wash water and allows it to be rinsed away.

That simple action is the foundation of an enormous amount of everyday cleaning.

Important Info

Use it for

  • Everyday surface cleaning
  • Hand wash
  • Dishwashing liquid
  • Foaming soap
  • Wool and delicates washing
  • Floors and other washable surfaces
  • Cars and outdoor cleaning
  • Suitable body and pet wash recipes

❎ Don't mix soap directly with acids

Keep Castile Soap separate from Citric Acid and vinegar.

Acid reacts with true soap and changes it back towards its original fatty acids, reducing the surfactant action you actually need for cleaning.

Both ingredients are useful. They simply work better at different stages.

Soap first to lift grease and dirt.
Acid afterwards when you need to tackle mineral residue or limescale.

💧 Hard water can change the result

True soap reacts with calcium and magnesium in hard water. This can reduce its cleaning performance and create the familiar cloudy residue called soap scum.

If you have hard water, understanding this matters. Ingredients such as Washing Soda and Borax can help manage those minerals in the appropriate cleaning recipes.

☁️ Don't worry if it goes cloudy

Our Castile Soap contains a high percentage of olive oil and may turn cloudy or develop white sediment in colder weather.

This is normal and doesn't mean the soap has spoiled. As the temperature increases, it will generally return to its usual appearance.

🫙 Storage

Keep tightly closed in a cool place away from direct sunlight.

When you dilute Castile Soap with water to make another product, make sensible quantities rather than unnecessarily large batches.

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One bottle. Far fewer products.

Keeping Castile Soap at home means you can make many of the products you use most often from one simple base, giving you greater control over what you clean with while spending less, storing less and throwing away less.

Gentle enough for personal care, useful enough for cleaning

Its olive-oil-rich soap base means the same ingredient can move from your cleaning spray to hand, body and pet-wash recipes, reducing the need for another separate product every time the job changes.
Gentle enough for personal care, useful enough for cleaning
Its olive-oil-rich soap base means the same ingredient can move from your cleaning spray to hand, body and pet-wash recipes, reducing the need for another separate product every time the job changes.

More control for sensitive homes

Start with a true soap made from just a handful of known ingredients rather than multiple specialised formulations containing added fragrance, dyes and other extras you may not want.
More control for sensitive homes
Start with a true soap made from just a handful of known ingredients rather than multiple specialised formulations containing added fragrance, dyes and other extras you may not want.

Stop paying for water

Most everyday liquid cleaners arrive already heavily diluted. Castile Soap is concentrated, so you add the water yourself and turn one bottle into litres of sprays, hand wash, dish liquid and more.
Stop paying for water
Most everyday liquid cleaners arrive already heavily diluted. Castile Soap is concentrated, so you add the water yourself and turn one bottle into litres of sprays, hand wash, dish liquid and more.

A simpler choice for what goes down the drain

Readily biodegradable, and choosing a simple soap formulation can reduce reliance on synthetic surfactants that may have greater aquatic-toxicity concerns.
A simpler choice for what goes down the drain
Readily biodegradable, and choosing a simple soap formulation can reduce reliance on synthetic surfactants that may have greater aquatic-toxicity concerns.
Handmade Dish Liquid and Dish powder on stylish amber glassware with eco-friendly dish brush all for green cleaning
All purpose spray kit with amber glass spray bottles and amber glass bottle of Castile soap in a wooden box with some cleaning rags.

Ways you'll use it...

The ingredient to reach for to tackle odours and oil spills.

All-Purpose Spray

Add a small amount of Castile Soap to water for the everyday cleaner you'll reach for most. Use it to lift fingerprints, grease and general grime from surfaces.
All-Purpose Spray
Add a small amount of Castile Soap to water for the everyday cleaner you'll reach for most. Use it to lift fingerprints, grease and general grime from surfaces.

Dishwashing Liquid

Combine Castile Soap with Glycerine and Xanthan Gum to make a thicker sink-side dish liquid that lifts oily food residue and grease.
Dishwashing Liquid
Combine Castile Soap with Glycerine and Xanthan Gum to make a thicker sink-side dish liquid that lifts oily food residue and grease.

Hand & Body Wash

A small amount of Castile Soap and water in a foaming pump creates a soft foam that spreads easily, letting the dispenser do more with less soap.
Hand & Body Wash
A small amount of Castile Soap and water in a foaming pump creates a soft foam that spreads easily, letting the dispenser do more with less soap.

Clean floors, cars & outdoor surfaces

Add it to water whenever you simply need soap to lift everyday oils and dirt from larger washable areas.
Clean floors, cars & outdoor surfaces
Add it to water whenever you simply need soap to lift everyday oils and dirt from larger washable areas.

Understand why this works

Learn how Castile Soap surrounds oils and dirt so water can carry them away, what makes true soap different from detergent and why hard water and acids can completely change how it performs. Understanding that one simple surfactant action explains why the same bottle can clean everything from your hands and dishes to benches and floors.

  • 5 stars: 21 (95%)
  • 4 stars: 1 (5%)
  • 3 stars: 0 (0%)
  • 2 stars: 0 (0%)
  • 1 star: 0 (0%)
R
Rachel O.
Great quality and price

I've been using this for a year or so now, for hand and body wash and bench spray. Love the quality and knowing if my kids ate it they wouldn't get sick!

J
Jill G.
I really enjoy making my

I really enjoy making my own household cleaning products - all the ingredients from Under Your Sink are top notch!!

S
Susanne W.
Great product

I like to buy aussie made, made my first batch of dishwashing liquid and had soap from the website. Couldn’t be happier. The service Analise provides is outstanding.

S
Sally T.
Fantastic Service and Products

Fantastic Service and Products

M
Michelle B.
Arrived in perfect condition and just made my first soap!

These were exactly what I’d hoped for - excellent quality, everything feels really well made. And thank you for the extra little gift. So generous and kind!! xoxo

R
Riina A.
I love this Castile Soap!

It’s a beautiful product and so versatile - I mostly use it to make my liquid soap as well as spray and wipe.

T
Trish F.
the best

have recently started using the Castile soap and will be ordering again. great product...fast delivery from Under Your Sink ....packaged perfectly to make its journey in one piece.

N
Naomi P.
Excellent product

Great product from fantastic ethically minded company.

M
Marie W.
Great product, thank you

Great product, thank you

A
Ange O.
Superior quality

Love the quality of this product!
Has a beautiful lush texture which increases its versatility. The large glass bottle looks amazing

K
Kim D.R. (Australia)
Castile Soap Laundry Liquid

The first time I have purchased this soap so don’t really have anything to compare it with. i made some foaming hand wash with it, and came out really well. Very nice and soft. I made some homemade laundry liquid with it this
morning. Very sudsy! Will cut down the amount of Castile soap if I make this again.

L
Linda M.
Lovely Pure Product

Very versatile, excellent quality. Good value.

S
Sheryn P.
My way

I use this to make my own multi-purpose spray and dish liquid. I love how it cleans and being able to use different essential oils depending on where used or my mood.

D
Dehera
Feels good to help environment

I love to be able to do my own shampoo and my dishwasher liquid.... not only I am not using any harsh chemicals in my hair but also feels good not to damage the environment (castile soap comes in a reusable glass bottle).

M
Mary M.
Castile soap

I have used another brand but this brand is far superior. It seems soapie! If that’s a word. I love it for my dishwashing liquid and I also use to wash my hair. Just a little bit goes a long way. Mary

E
Esther D.
Great product at a great

Great product at a great price! Loving it!

N
Nicole R.
The most gentle product!

This changed my families life.

N
Nicole B.
Love it

Making my own multi purpose sprays and then hand wash is absolutely amazing and it’s all natura....love it

C
Caron M.
Love that i can mix

Love that i can mix up my own hand wash with some essential oils !

M
Muriel B.
Castile soap

Great product, very versatile. Can’t wait to try making body wash with it. Love the amber glass bottle it comes in too

L
Laura H.
Castille Soap

Love this product! It is so versatile! I love using it to make all purpose cleaning spray where I can add my favourite essential oils. Also use a capful in my mop bucket with Eucalyptus or lemon essential oil to mop my timber floors. So much healthier way to clean. I used to use Domestos not realising how toxic it was.

N
Nicole R.
Essential in every home

i buy this every time i shop here. its the best quality and i use it with most of my cleaning products. i love the new big bottles too!!