Here you'll find an easy-to-follow tutorial on how to make breastmilk soap in only 5 minutes! Making your own soap is a great way to use up any extra milk you might have plus it's gentle on baby's skin.

No matter whether you're an over-supplier or an under-supplier, every breastfeeding momma has the same fear: What if I run out of milk?
So we pump and freeze and pump and freeze every drop until our babies wean and we realize we have a freezer full of milk. Now what?
Well, over the years I've come up with a few uses for surplus breast milk, such as giving a breast milk bath or making breast milk lotion, but today I'm going to show you how to make breast milk soap. Which is a great way to make beautiful soaps using your own milk as a fresh ingredient. You can even customize it to your heart's desire by adding essential oils, honey and oatmeal.
(If you're an experienced soap maker looking to make cold process soap using breast milk, scroll to the middle of the post to find the instructions. Everyone else, stick with me 😉
Jump to:
Breastmilk Soap Benefits
Human breast milk is amazing - some even refer to it as liquid gold! It's the perfect first food, but It's also beneficial for baby's sensitive skin and a number of skin conditions.
You might have heard of breast milk’s powerful immunological properties, but there are many more beneficial components found in breast milk. Things like proteins, amino acids, prebiotics, enzymes, antibodies, fatty acids, vitamins and minerals... the list goes on and there are still things that haven't been studied yet.
Breast milk soap is very nourishing and gentle on the skin since it contains many skin-loving components of breast milk, like fatty acids, enzymes, vitamins and minerals.
"Just put some breast milk on it" is probably the number one advice among nursing moms. With good reason: breast milk has been shown to be effective in treating infant eczema, can help alleviate pink eye, dry skin, diaper rash, cradle cap, and baby acne and can even reduce the risk of small cuts getting infected (Source: Medela)
What you'll need
- Pyrex Measuring Cup
- Sharp Knife
- Digital Kitchen Scale
- Whisk
- Microwave or Double Boiler/ Water Bath
- Meat Thermometer (optional)
- Sunflower Silicone Mold or Teddy Bear Mold
- Rubbing Alcohol in Spray Bottle (optional)
Ingredients
- 200g / 7oz Clear Melt & Pour Soap Base or Shea Butter Soap Base
- 150 ml / 5oz Breast Milk (room temperature)
- ½ teaspoon Honey (optional)
- 1 tablespoon ground Oatmeal (optional)
- 15 drops Chamomile Essential Oil or lavender essential oil (optional)
How to Make Breast Milk Soap
If you're planning to use oatmeal, add ¼ cup of old-fashioned oatmeal to a coffee grinder and blend until you have a fine powder.
Now, onto the soapmaking:
- Cut the soap base into small chunks and measure out 200g
- Melt the soap base in the microwave on 20 second burst stirring in between each burst or melt on medium heat in a double boiler or water bath
- Let the soap base cool down to about 130℉/ 55℃ in order not to scorch the milk
- Add breastmilk and stir
- Whisk in honey and oatmeal (if using) until there are no more clumps
- Add essential oil and stir
- Pour soap into mold
- Spritz the top with rubbing alcohol to minimize air bubbles (optional)
- Let the soap cool down and harden
- Then unmold
- Store in Ziplock bag in the fridge until ready to use
How to Store Melt and Pour Breastmilk Soap
I recommend storing your soap bars in a small zip lock bag in the fridge. If you know you won't be using your soap any time soon, I suggest storing it in the freezer. Once a soap bar is in use make sure it dries completely between uses in a well-draining soap dish. I like to use smaller silicone molds, so that the soap bars can be used up faster.
If you notice the soap turning a darker color or smelling off, please discard it.
Melt and Pour Soap vs. Cold Process Soap
Now, let me be very clear: you need lye to make soap! Real soap is created when lye (sodium hydroxide) and fat are mixed together, the resulting chemical reaction will turn both ingredients into soap.
The difference is that with a melt and pour soap base the soap making process (or the handling of lye) has already been done for you. With cold process soap you're truly making soap from scratch. Both are a great way to make your own soap using natural ingredients.
For the purpose of making soap from breast milk, both methods have very distinct pros and cons, however:
Melt and Pour: The advantage of this method is that you can add your breast milk straight to the melted soap base. The milk will not undergo any chemical changes and will retain most of it's beneficial properties. That also means that you will have a shorter shelf life and is best stored in the fridge.
Cold Process: With this soap making method the breast milk is added to the lye and undergoes the process of saponification (lye and fat turning to soap). Sadly, the milk will change too and loose most of it's skin-loving properties. BUT it will still result in a gentle and creamy soap.
Nobody really knows which beneficial milk molecules make it through the soap making process and how many. But there are lots of folks that report great skin benefits of handmade goat milk soap, for example. So, some of it must remain in the finished soap. Cold process soap has a shelf life of at least 6 months (if stored away from humidity and sunlight) even with the addition of breast milk.
Cold Process Soap Recipe
I know what you're thinking now: Will all these wonderful enzymes, antibodies and the magic pixie dust make it through the soap making process? The answer is: no, they will probably not make it through the "lye monster". Cold process soap undergoes a serious chemical process when oils are being mixed with lye that creates a PH environment where microbes (good and bad) can't live.
The good news is: breast milk is still a great additive in soap, think cows or goats milk on steroids. It contains more fats and sugars than regular milk which contributes to a smooth creamy abundant lather. And it also has lots of vitamins (A,C,D and E) that are great for your skin.
This soap recipe is another variation of a Bastille soap. Meaning a soap that is made with 75% or more of olive oil, but not a Castille soap which contains 100% olive oil. As I mentioned in my Baby Bastille Soap Tutorial, I'm not a big fan of Castille soap - the lather feels slimy to me and I have no patience for the long cure time 😉
To give this soap a nice bubbly lather and hardness boost I added coconut oil at 20%. Coconut oil sometimes feels drying to some folks, but the high percentage of olive oil and breast milk in this recipe make this soap feel creamy and gentle.
How to Add Breast Milk to Any Soap Recipe
In this tutorial I provide a soap recipe for you, but if you'd like to use breast milk (or any kind of milk) in another recipe you can. Simply follow the same steps that I will outline here.
For this recipe we're going to replace the entire water content of the soap with breast milk. In order to do that we'll have to take some extra steps in order for the milk not to scorch when mixed in with the lye. You know when the milk starts to scorch when it turns a yellow color and gives off a strong ammonia smell.
- Freeze milk in an ice cube tray
2. Place frozen milk cubes in a medium sized container (plastic or stainless steal)
3. Place container in an ice bath
4. Measure lye into a small container
4. Little by little add lye to the frozen milk while continuously stirring. The more time you take with this the less the chance of scorching.
5. After the breast milk is completely melted stir for another minute to make sure the lye is completely dissolved
If this is the first time making cold process soap with lye, I suggest you go back and read up on lye safety, recommended equipment and how to make homemade soap.
Disclaimer: This post contains affiliate links, meaning at no extra cost to you will I earn a commission if you click through and make a purchase.
Equipment needed:
- Ice cube tray
- 3 medium sized containers (one of them can be glass (pyrex) the others plastic or stainless steel)
- One small plastic cup (to measure lye)
- One plastic spoon
- Spatula
- Immersion blender
- Accurate digital kitchen scale
- Sunflower single cavity soap mold
Ingredients for 6 Soaps weighing 3 oz / 85 g each:
This recipe is superfatted at 5% and uses a lye concentration of 38%.
- Breast Milk: 2.85 oz / 81 g
- Lye: 1.75 oz / 50 g
- Olive Oil: 10.16 oz / 288 g
- Coconut Oil: 2.54 oz / 72 g
- Chamomile Essential Oil: 11 g
Instructions:
- Freeze milk in an ice cube tray
- Place frozen milk cubes in a medium sized container (plastic or stainless steal)
- Place container in an ice bath
- Little by little add lye to the frozen milk while continuously stirring. The more time you take with this the less the chance of scorching.
- Stir for another 5 minutes to make sure all the lye is properly dissolved and set aside to cool
- Melt coconut oil over low heat in a water bath or on short bursts in the microwave
- Add olive oil
- Add essential oils
- Place soap mold on a cutting board
- When lye solution and oils have cooled so they're not hot to the touch, add the lye solution to oils
- Stick blend until medium trace (light pudding consistency) is achieved
- Fill soap batter into the mold cavities
- Tap cutting board with soap mold on the counter to release air bubbles
- Place soap in freezer overnight
- Leave out at room temperature for 24 hours and unmold
- Cure for 6 weeks
- Enjoy!
Breastmilk Soap Recipe (printable)
This breast milk soap recipe is an easy and great way to use any leftover breast milk you might have. The no lye recipe is quick and easy especially for beginners.
Materials
- 200g / 7oz Shea Butter Soap Base or Clear Melt & Pour Soap Base
- 150 ml Breast Milk (room temperature)
- ½ teaspoon Honey (optional)
- 15 drops Lavender or Chamomile Essential Oil (optional)
- 1 tablespoon ground oatmeal (optional)
- rubbing alcohol in spray bottle (optional)
Tools
- Pyrex Measuring Cup
- Sharp Knife
- Digital Kitchen Scale
- Whisk
- Microwave or Double Boiler/ Water Bath
- Meat Thermometer
- Sunflower Soap Mold
Instructions
Melt & Pour Breastmilk Soap
- Cut the soap base into small chunks and measure out 200g
- Melt the soap base in the microwave on 20 second burst stirring in between each burst or melt on medium heat in a double boiler or water bath
- Let the soap base cool down to about 130℉/ 55℃ in order not to scorch the milk
- Add breastmilk and stir
- Add honey and oatmeal (if using) and whisk
- Add essential oil and stir
- Pour the soap into the mold
- Optional: Spritz the top with rubbing alcohol to minimize air bubbles
- Let the soap cool down and harden
- Store in a ziplock bag in the fridge until ready to use
Rebecca Dillon
What a unique and fun idea for new moms. Thanks for the recipe.
Celine
Thank you 😊
Lisa Garland
How long does the soap last (does it go bad?)
Celine
Hi Lisa, At least 6 months when stored in a cool dry place
Ashley
Hi, can this recipe be used as hair shampoo as well?
Celine
Yes it can.
Celine
Hi Lisa, for at least one year. If you notice orange spots and a bad smell it's time to throw it out.
Frances Mercado
Can I add oatmeal? If so how much and how? Also My melt and pour is honey base, do I need the honey still?
Celine
Hi Frances, I would add 1 Tbsp of colloidal oatmeal to one pound of soap. I find the raw honey added to soap has antibacterial properties, but you can leave it out.
Frances Mercado
Also, why is the breastmilk qty so small, pther recipes call for 1 cup of bm.
Celine
That’s a very good question. I have tried to increase the amount of milk and the soap wouldn’t set up. Some people don’t recommend adding any liquid to a melt and pour soap base.
Rosemary Monday
I always find your recipes interesting. Thanks
Celine
Thank you 🙂
Olivia
If I use the pour and melt with breast milk option, what is the best way to store the soap? Should I leave it in the fridge, freezer or can I leave it out. I noticed you said , 6 months until it goes bad.
Celine
Hi Olivia, I would leave it in the fridge. Hope that helps.
Eva
Would this be harsh on the eyes for babies, since it’s not tear free? Unless it is?!
Celine
It's not specifically tear free. I recommend keeping it out of baby's eyes as much as possible.
Arh
When you say to mix the lye with the frozen breastmilk for cold process, do you mean a lye solution?
Thank you!
Celine
You add the lye beads/flakes to the frozen milk little by little. The heat created by the chemical reaction will slowly melt the breastmilk and create the lye solution that you then add to the oils. Hope that helps!
Arhianna A Brown
Thank you! I'm going to try today. If I'm going to make a loaf, do you know if I should double or triple the recipe? Thank you!
Celine
It depends on the size of your loaf. Here's how you can calculate how much soap you're going to make https://www.modernsoapmaking.com/blog/how-to-resize-a-soap-recipe-for-your-soap-mold-imperial-and-metric
Nalda Keesee
I made breastmilk soap and I storage in containers in the freezer but it's getting little ice crystal on it is that ok or should I put it in the fridge
Celine
I'm guessing it's ok. If you want to avoid it next time wrap each bar in plastic wrap as airtight as possible.
Amy
Hey! Does the soap made with the pour and melt method lather? Thank you for this recipe hoping to try it with my left over freezer supple!
Celine
It does lather, but not a whole lot. Let me know how it turns out.
Aria bassett
How to make this if your milk is already frozen in 6oz bags
Celine
You will have to defrost the milk, you can add 6 oz of milk to 250g or 1/2 pound of soap.