Does Castile Soap (Like Dr. Bronner’s) Really Work for Many Household Uses at Once?

Several months ago, I had a handful of users in rapid succession contact me and ask whether or not I had used castile soap as a multipurpose hygiene soap and household cleaner. They recommended all kinds of uses for it: bath soap, hand soap, window washing, dish washing, laundry soap, even toothpaste.

Before we get too far into this, let’s back up and talk about what castile soap actually is.

Castile soap is a particular type of soap made strictly from vegetable oils. Soap of all kinds is made from various fats – often animal fat, but almost any kind of fat or oil will work – mixed with some kind of alkali metal, usually lye. Castile soap, then, is just a sub-type of soap that uses vegetable oils for the fat – olive oil, canola oil, and so on.

What’s special about castile soap? Because it’s made with just vegetable oil, castile soap has a more neutral pH than most soaps, which tend to register higher on the basic end of the scale. Castile soap is virtually always biodegradable, which isn’t always true for other soaps.

What about the actual use of castile soap, though? How does it compare with other soaps? That’s what we’re going to talk about today.

Before we get started, I wanted to point out that the Dr. Bronner’s website offers some suggestions for diluting castile soap for various uses. I didn’t discover this until later in my experimentation, but most of the dilutions I ended up finding acceptable were similar to what their website suggested; if anything, mine were somewhat more concentrated, but not enormously so. A lot of the dilutions on the website were 1 part soap to 16 parts water, while (as you’ll see) I used a lot of 1 part soap to 8 parts water dilutions.

First, the Cost

During this exercise, I used two different brands of castile soap, Dr. Bronner’s and Public Goods. More specifically, I used this 16 ounce bottle of Public Goods castile soap for $8 and this type of Dr. Bronner’s castile soap. The Public Goods castile soap cost me about $0.50 per ounce and the Dr. Bronner’s soap, bought in a much larger quantity, cost about $0.32 per ounce.

In other words, it’s cheaper to try the Public Goods kind, but if you’re using it for lots of things around the house, Dr. Bronner’s was easier to find at a low rate.

The important thing to note here is that you almost always seriously cut castile soap with water before using it. Most of the things I did with castile soap involved diluting it with three parts water to one part castile soap before using it. It made for a watery soap, but it also meant that a quart of castile soap became a gallon of diluted soap, and it was the diluted soap that I actually used for everything.

There are quite a few brands of castile soap out there. I didn’t try them all, just these two, but I found that these two were extremely similar in terms of practical use.

So, let’s start talking about some uses.

Hand Soap

Most of the time, we use a 10 ounce store brand liquid soap bottle with dispenser that we buy for $0.99 at Target. Thus, our cost for this is about $0.10 per ounce. It’s a good hand soap that we’ve been happy to use.

To compare the two, I diluted the castile soap with three parts water to one part castile soap and filled up an empty dispenser. With the Dr. Bronner’s soap, this reduced the cost to about $0.08 per ounce of diluted soap; the Public Goods soap was about $0.12 per ounce of diluted soap. So, the price here is comparable.

We used a normal soap dispenser at first and I found that the diluted castile soap did a really good job of cleaning your hands. In fact, they almost felt squeaky clean afterwards, even after using just a bit of soap, and whatever I had on my hands was easily washed away. They felt and smelled clean afterwards. The only drawback was that the soap was really watery and it was easy to make a mess at the side of the sink, as the watery soap easily spilled out of your hand.

I then switched to a foaming hand soap dispenser and this worked far better. The foaming soap created by the dispenser was basically the same as any other foaming hand soap in terms of quantity and neatness, and it produced the same “squeaky clean” feeling from hand washing.

I read that you can actually dilute it even further, so I tried diluting it to eight parts water to one part soap (this reduces the price to $0.04 to $0.06 per ounce for castile soap). In other words, I added two tablespoons of the castile soap to a cup of water and used that in the foaming dispenser. This worked perfectly fine, too, though it didn’t “suds up” as much as the more concentrated soap. It did leave a faint “squeaky clean” feeling. I would be happy to have soap concentrated at this level as a hand soap for bathrooms and the kitchen in my home.

Recommendation: get a foaming hand soap dispenser before trying it, but castile soap does a good job when you dilute it with 8 parts water to 1 part castile soap and it’s very inexpensive

Body Wash / Shower Soap

My experience with using castile soap as a body wash in the shower was very, very similar to my experience using it as a hand soap.

First of all, for the last few years, I’ve primarily used bar soap – a wide variety of it. I’ve really only ever disliked one particular kind of bar soap and it’s been long discontinued. A bar of soap, depending on the size, lasts a month or two of daily use. I’d estimate an average bar of soap that I use costs $3, again, varying based on size (I honestly usually buy soap based on how it smells and the price). Thus, I’d say a single shower’s worth of soap costs about $0.10 for me, give or take a little.

My first attempt at using castile soap in the shower was identical to my first hand soap attempt – three parts castile soap to one part water, in a normal squirt bottle. The issue I had with that arrangement is that the soap was so runny that I’d lose a lot of it while lathering up as it would just run down the drain before making a lather.

Thus, I wound up doing the same thing in the shower that I did with hand soap. I wound up cutting it at the same rate – eight parts water to one part castile soap – and putting it in a foaming dispenser. I found that I had to use quite a lot of squirts of it to get myself satisfactorily clean, but the expense of each squirt was minute. As I noted earlier, an ounce of this watered down castile soap is about $0.05 per ounce, so I’d have to use two ounces in a shower to match the cost of using bar soap. I probably used more than an ounce, but not two (based on the speed of refilling the container), so castile soap wound up being a small savings in the shower.

Again, it provides kind of a “squeaky clean” feeling which felt unusual on my skin. I felt clean, but it somehow felt different than the soaps I was used to – not bad, but different. My wife noted that I smelled citrus-y after a shower a couple of times, which made sense since I was using citrus castile soap.

After several uses, I think it might have been drying out my skin a little bit, but it was hard to really determine if that was due to other conditions or the castile soap. I think it might have a very minor skin drying effect, but it would probably only be an issue to someone with sensitive skin.

Shampoo / Conditioner

I tried using the castile soap mix described above as a replacement for shampoo as well. I used the same cut as described above – eight parts water to one part castile soap – and used it out of the same foaming dispenser.

It seemed to get my hair clean, though it didn’t feel as “fluffy” as it usually did. That’s probably due to a lack of conditioner.

I keep my hair pretty short, so I didn’t need to use much of it. After several showers, I didn’t notice any effects like dandruff or anything. I don’t think my hair is particularly oily or fine or coarse or anything – it’s pretty average hair. I think I would use it as a shampoo substitute, but if I wanted my hair to feel more soft, I’d also want to use a conditioner in conjunction.

The quantity of shampoo and castile soap I use for each shower is very small, due to my hair being short, so I think the cost difference is negligible. I usually use Suave for Men as it smells fine and I don’t have any particular special hair needs.

General Purpose Household Cleaner

I initially tried using an eight parts water to one part castile soap mix in a spray bottle as a general household cleaner, but I found that it was too soapy for doing things like cleaning up little messes and stains or getting a mark off the wall.

What I ended up doing is diluting it again, down to 16 parts water to 1 part soap, or one tablespoon of soap per cup of water in the spray bottle. This was fine, but still almost a bit too soapy. If I were to make another batch, I’d probably make 24 parts water to 1 part soap, or a cup and a half of water to one tablespoon of soap.

It basically tackled every small cleaning job I threw at it. It cleaned up a dog mess, coffee stains, some mystery mark on the wall, and several other little things. It also did a pretty bang-up job cleaning a window with a rag, though this is where I noticed it being almost too soapy. I think the 24 parts water to 1 part soap would be even better for windows in particular.

A final note: do not mix this with vinegar. I often use diluted vinegar as a general household cleaner, but vinegar and castile soap do not mix well at all. You end up with a white film on everything it touches and it doesn’t clean much at all.

Laundry Soap

I usually either use store brand laundry soap or detergent or I use my own homemade mix of equal parts soap flakes, borax, and washing soda – a tablespoon of that mix is all that’s needed for a load and it’s substantially cheaper than even store brand laundry detergent. I can usually wash a load of clothes for about $0.05 of soap/detergent at most.

I tried washing a few loads of normal laundry with a tablespoon of straight castile soap, not watered down at all, per load. For laundry that was barely dirty, it did a fine job and came out without any noticeable odor or any other problem. I did notice that on gym clothes, there was a very faint residual odor on a couple of the items from … well, gym odor. A second washing seemed to get rid of it, or at least lowered it to the level I couldn’t detect any more.

I also noticed that a muddy pair of jeans did not get completely clean. However, on a later load, I had another muddy garment (a t-shirt this time) and I scrubbed just a little castile soap right on the muddy spots and it came out clean. I also had a shirt with some dried blood from a nosebleed and it seemed to come out clean as well after being scrubbed right on the bloodstain with a tiny bit of castile soap.

I don’t think that castile soap on its own would make for a good laundry soap. However, I think that a mix of castile soap, borax, and washing soda would do a pretty good job, as it would be pretty equivalent to the homemade laundry soap mix I already use.

Dish Soap

Castile soap is not intended for dishwasher use. You don’t want a cleaner that lathers in the dishwasher, so although castile soap doesn’t lather much, it does lather a little, and thus you don’t want to do it in there.

I tried it for handwashing dishes at an 8 parts water to 1 part soap ratio and I thought it did a fine job on almost all of my dishes. They got nice and clean with no troubles.

On really dirty caked-on stuff, the diluted soap didn’t really work. It would get some of it off after a lot of scrubbing, but it wouldn’t get the worst stuff off. I ended up using full strength castile soap on a few things and that seemed to do the trick, but at that cost, normal dish soap is more cost-effective.


I tried this, using one drop of castile soap, because it was recommended both on the Dr. Bronner’s site and several other websites that I read. Never again. Don’t do this. Yeesh.

Toilet Bowl Cleaner

This was the one cleaning job where the castile soap kind of flunked the test. It did almost nothing to get a mildly dirty toilet clean, whereas a toilet bowl cleaner did the job really well.

I tried even using pure castile soap in the toilet but, for some reason, it almost did nothing at all to affect stains in there, even with a ton of scrubbing. I switched to using a toilet bowl cleaner and, while the stain didn’t come off easily, it did gradually come off after some scrubbing and I wondered if it would have been even easier had I not used castile soap first.

Don’t bother using castile soap to clean a toilet unless it’s very mildly dirty.

So, What Are We Using Castile Soap For?

At this point, I intend to use the rest of our castile soap for a few specific purposes.

It’s definitely going to stick around in a foaming soap dispenser for hand soap. In fact, it’s a switch I’m considering making as a permanent change. I think it does a great job at this with an eight parts water to one part soap ratio (basically two tablespoons of soap in a cup of water in the dispenser, sloshed around a little) and it’s really cheap.

I’m almost definitely going to continue using it as a general household cleaner. In the future, I’m going to keep it diluted to a 24 parts water to 1 part soap ratio – a cup and a half of water to a tablespoon of soap – as that seems to work well for small household messes and windows.

I’m on the fence about using it as a shower soap. It seems to do fine in the shower for me, but I don’t think it’s saving me much money and I’m not sure whether it will dry out my skin over a lot of uses. I’ll probably use up what I have and go back to bar soap.

I’m not going to use it as a shampoo, a laundry soap, a dish soap, or as a toilet bowl cleaner. I think I’ll go back to my original shampoo/conditioner combo and my previous laundry soap and dish soaps, and I thought it didn’t work well at all as a toilet bowl cleaner.

So, basically, it’s going to be a hand soap and a general household cleaner for us going forward, though I will continue to use it as a “body wash” in the shower for a while. I would use it for the other purposes in a pinch (except for toothpaste) if needed, but I think other solutions do the job better.

Trent Hamm

Founder & Columnist

Trent Hamm founded The Simple Dollar in 2006 and still writes a daily column on personal finance. He’s the author of three books published by Simon & Schuster and Financial Times Press, has contributed to Business Insider, US News & World Report, Yahoo Finance, and Lifehacker, and his financial advice has been featured in The New York Times, TIME, Forbes, The Guardian, and elsewhere.