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.

It’s milk central at Tweak & Tinker HQ these days. There’s milk spit up, milk throw up, milk leakage and pumping. Let me just say: We don’t have a milk shortage around here.
Sometimes I find myself with a bottle in the fridge that I don’t need. Instead of letting it go to waste I decided to put it to good use in a soap recipe.
Why Would you Want to Make Soap with Breast Milk?
Human milk – aka breast milk – is absolutely amazing! It nourishes a tiny infant with everything she needs to grow, grow and grow some more into a chubby smiley wiggly little human. It contains stuff that is borderline magical and it constantly keeps changing as the baby grows to meet exactly their needs – genius!
Here are just some of the components found in breast milk: immune-boosting live cells (millions of them), proteins, amino acids, prebiotics for gut health, enzymes, antibodies, fatty acids, vitamins and minerals… the list goes on and there are still things that haven’t been studied yet.
“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 rashes and acne and can even reduce the risk of small cuts getting infected (Source: Medela)
If you’re a beginning soap maker or simply not comfortable working with lye. Then this no lye breast milk tutorial is great for you! (For the cold process or lye version of this soap – keep scrolling 😉

How to Make Breastmilk Soap Without Lye
Equipment needed:
- Pyrex Measuring Cup
- Sharp Knife
- Digital Kitchen Scale
- Silicone Spatula
- Measuring Spoons
- Microwave or Double Boiler/ Water Bath
- Meat Thermometer
- Sunflower Soap Mold
Ingredients for 6 sunflower shaped soaps:
- 500g / 17oz Clear Melt & Pour Soap Base
- 6 Tbsp Breast Milk (you can use up to 10 Tbsp, but the soap will be softer)
- 1/2 tsp Honey
- 30 drops Chamomile Essential Oil (optional)
Instructions:
- Cut the soap base into small chunks and measure out 500g

2. Melt the soap base in the microwave on 30 second burst stirring in between each burst or melt on medium heat in a double boiler or water bath

3. Let the soap base cool down to about 130℉/ 55℃ in order not to scorch the milk

4. Add 5 Tbsp of breastmilk and stir

5. Add 1/2 tsp of honey and stir

6. Add 30 drops chamomile essential oil and stir

7. Pour the soap into the mold

8. Spritz the top with rubbing alcohol to minimize air bubbles and sweating of the soap

9. Let the soap cool down and harden
10. Then unmold

11. Store in an airtight container or ziplock bag in a cool dry location
What is the Shelf Life of the Soap? Will it Go Bad?
In my testing I haven’t found that the soap goes bad. The initial soap I made 6 weeks ago hasn’t changed color nor did it develop a bad odor. I kept mine very well wrapped in a cool place. The addition of honey in this recipe adds natural preservative properties which helps keep the soap fresher longer. If you wanted to you could also keep it in the fridge.
If you detect any foul smell or color change in your soap, please don’t use it and discard.
How to Make Breast Milk Soap Using Lye (Cold Process Method)
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.

About This Breast Milk Soap Recipe
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

How to Make Soap Using Breast Milk
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 try my beginner’s tutorial.
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 oil
- 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!

Melt & Pour Breast Milk Soap
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
- 500g / 17oz Clear Melt & Pour Soap Base
- 6 Tbsp Breast Milk (you can use up tp 10 Tbsp, but it'll make the soap softer)
- 1/2 tsp Honey
- 30 drops Chamomile Essential Oil (optional)
Tools
- Pyrex Measuring Cup
- Sharp Knife
- Digital Kitchen Scale
- Silicone Spatula
- Measuring Spoons
- 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 500g
- Melt the soap base in the microwave on 30 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 5 Tbsp of breastmilk and stir
- Add 1/2 tsp of honey and stir
- Add 30 drops chamomile essential oil and stir
- Pour the soap into the mold
- Spritz the top with rubbing alcohol to minimize air bubbles and sweating of the soap
- Let the soap cool down and harden
- Store in an airtight container or ziplock bag in a cool dry location
What a unique and fun idea for new moms. Thanks for the recipe.
Thank you 😊
How long does the soap last (does it go bad?)
Hi Lisa, At least 6 months when stored in a cool dry place
Hi Lisa, for at least one year. If you notice orange spots and a bad smell it’s time to throw it out.