Castile vs. Bastille Soap: What is the Difference? Which is Best? PLUS Easy Hot Process Recipes for Both Kinds of Soap that Work!
A friend of mine, who has started her own soap making business made some Castile soap for the first time the other day. My ebook, How to Make Hot Process Soap, was her jumping off point on her soap making journey, and I'm really excited for her!
She is now making cold process soap as well as hot process soap, and she recently decided to give some Castile soap a try. She told me Castile soap requires a VERY long cure time, like up to a year! Castile soap can be a bit finicky to make, I have heard.
Being the inquisitive soap maker that I am, I had all these questions:
Does Castile soap REALLY take a whole year to cure?
If it takes that long for cold process Castile soap to cure, then MUST it take a long time for hot process Castile to cure too?
And which is better? Castile? Or Bastille?
For Pete's Sake: What is the difference, anyway?
What made me wonder about Bastille vs. Castile soap was I was considering making some more of my Bastille-Honey soap which really is a lovely, skin soothing soap. Then I thought: Maybe I should try Castile soap? Or Castile Honey soap?
Well, I decided to keep both soap recipes (Bastille & Castile) super simple (recipes shared below), and did a great little experiment to answer all these questions by making both kinds of soaps.
I NOW have the answers! Well....except that I still don't know if it REALLY does take a whole year for Castile soap to cure using the cold process method. I am just a hot process girl. That's for sure.
You know why I'm a hot process soap making girl? You can find out all about Cold Process vs. Hot Process Soap Making in this link---and maybe you can see why.
Also, if you are wanting to make soap, you’ll love to have the FREE life-saving Soap Making Checklist! You can get it at the end of the article.
FTC Disclosure: There are affiliate links scattered throughout this article. If you click through and make any kind of purchase, I may receive a small commission at no extra cost to you. Full Disclosures Here.
So here goes:
First, What is the Difference Between Castile and Bastille Soap?
GREAT question! I found out the answers to this one when I made my first Bastille-Honey Handmade Soap. (It turned out great, by the way.) Here are the differences:
What is Castile Soap?
Castile soap is made ONLY with pure olive oil, lye, and water. That's it. That's all. No more. Just three easy ingredients.
The sodium hydroxide (lye) and water solution effectively turns that lovely, rich olive oil into Castile soap. The characteristics of Castile soap are important to note because it is probably one of the most skin conditioning soaps on the planet. It is REALLY good for your skin.
However, because of this factor, it is also very weak in the cleansing and bubbling arena. It has a very creamy lather, but it's NOT bubbly, and it is not very cleansing either.
If you have extremely sensitive skin, then you will probably just love Castile soap. Otherwise, most folks I have run across are not fans of the stuff.
In fact, I have another friend who visited Italy (the home of Castile soap), and he brought back a "real" bar. It was a dark olive green, and for some reason, it just didn't smell that great---the olive oil was probably more pure (or not virgin) or something. Honestly, I was not impressed. But then, who am I to judge?
What is Bastille Soap?
Bastille soap is ALMOST like Castile soap except it has additional oils added to it. I read somewhere is that it is "bastardized" Castile soap (hence the name). To be true Bastille soap, it needs to be at least 75% Olive Oil.
This high level of olive oil STILL leaves you with a super conditioning bar of soap. What you can do is add the kind of oil that will help give your Bastille soap extra qualities that Castile soap just doesn't have. (Cleansing, anyone?)
To do this, you need to know the qualities of different oils. You can read about different oils in this article: 20 Best Oils to Use in Your Homemade Skincare Products.
Recipes for Castile Soap and Bastille Soap
OK, so I could truly compare the differences, I kept my recipes VERY simple. I didn't add any colorants or additives---except for a bit of Clove & Grapefruit essential oils at the end (because they happen to repel wasps, besides smelling delicious).
Each of these recipes makes only one pound of soap. If I'm not sure how the soap will turn out, I try to create smaller batches. You waste less ingredients that way. Plus, I was able to put them in the same soap mold too.
Here are the two recipes I made to compare:
Recipe for Castile Soap:
** 16 ounces of Organic Olive Oil (I get mine from Costco)
** 6.08 ounces of Distilled Water
** 2.06 ounces of Sodium Hydroxide (I use food grade because it just makes me feel better.) Sodium Hydroxide is the Lye.
Follow Hot Process Soap Making directions.
You can find excellent directions in these articles and book:
and my complete hot process eBook: How to Make Your Own Hot Process Soap with Confidence.
Basic Recipe for Bastille Soap:
** 12.8 ounces of Organic Olive Oil
** 3.2 ounces of Coconut Oil
** 6.08 ounces of Distilled Water
** 2.06 ounces of Sodium Hydroxide (Lye)
Follow the same directions for hot process soap as stated in the links above. I always have two soap making crock pots going at the same time, so I made both of these soap recipes at once.
Making more than one batch at a time is great because it's very easy to see the different behaviors of the various oils and lye solutions. You'd be surprised at the differences in soap behavior!
Castile vs. Bastille Soap: Which is Best?
In this section, I'm going to give you a quick bullet point rundown of each kind of soap. I'll be honest. I was surprised! Here goes:
Hot Process Castile Soap:
Castile Soap has long been heralded for its gentle skin loving nature. Made from pure olive oil (and no other oils whatsoever), Castile soap is tremendously beneficial for your skin. It may be the most conditioning soap available, as a matter of fact!
However, because of it's excellent skin conditioning properties, Castile soap has some downfalls:
It's a REALLY nice, hard bar of soap
It lacks cleansing ability
It does not bubble, rather it has a "creamy" lather
It took awhile to come to trace, but it cooled and hardened really fast. I used it that same night!
My skin LOVES this soap.
So, if you are willing to give on the cleansing and lathering soap qualities in exchange for some terrific skin softening and conditioning, perhaps Castile soap is for you!
Hot Process Bastille Soap (Made with Coconut Oil):
Bastille Soap is primarily made with olive oil, which means that no matter what other oils are mixed with it, it will still retain some amazing skin conditioning abilities. Bastille soap must have at least 75% olive oil, and the other oils can actually help offset the lack of cleansing of a pure Castile soap.
When I created my very simple Bastille soap recipe, I decided to use Coconut oil, which is a very common oil used in soap making.
Coconut oil is excellent in the cleansing and lathering areas---which means it's not the greatest choice for a skin conditioning oil. In fact, it can be a bit drying.
But when mixed with 75% (at least) olive oil, you will have a soap that is not only cleansing but still highly conditioning.
So, in a nutshell, this Bastille soap:
Is very cleansing while still being extremely conditioning and soothing for your skin
Has a great lather!
It is still a hard bar.
Took some time to come to trace, and I had to wait until the next day for it to be hard enough to use in the shower.
Love this soap! But I love my Bastille-Honey Soap more! Just saying.
Final Thoughts on Castile Soap vs. Bastille Soap
I love both of these soaps. I really do.
When I use this pure Castile bar, it feels like such a traditional (and Italian) way of bathing. But the Bastille soap is just wonderful, as it combines the rich skin soothing qualities of Castile soap, but you still have the cleansing ability and great lather that other oils can provide!
By the way---Bastille soap may not always have great qualities that offset the lack of cleansing of a Castile bar of soap. It's all about the additional oils used in the recipe.
I run my recipes through www.soapcalc.net so I can take a look and a preview at the soap qualities my recipe will have. They provide a great chart so you get an idea about how the soap will cleanse, lather, and condition skin. I can then determine if my soap recipe will most likely be a good one or not.
What do you think of the differences between Castile and Bastille soap? I'd sure love your opinions!
Happy soaping, my friends!
Hugs, Health, and Self-Reliance,
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