A gentle bath bomb fizzing in warm water can turn an ordinary evening into a home SPA experience, especially when it’s rich with milky, nourishing ingredients. This milk bath bomb recipe is one of my favorites: gentle, rich, and soothing, turning a simple soak into something magical that sparks joy. If you’ve been looking for a natural bath bomb recipe that’s easy to make and luxuriously nourishing, this one might just become your new favorite!
A Creamy, Cozy Ritual
Imagine a warm bath lit by candlelight, a relaxing playlist in the background and this lovely milk bath bomb releasing its soft fizz as the fragrance of sweetened milk wraps around you. The water feeling becomes nourishing, thanks to powdered milk and oils, while your skin is enveloped in a silky, hydrating hug.
Why This Milk Bath Bomb Is Special
This is more than just another bath bomb recipe. What makes this one different is its nourishing core. Powdered milk gives a velvety texture and leaves your skin feeling soft and conditioned. Milk has been used in beauty rituals since ancient times. Rich in fats and proteins, it helps nourish the skin while maintaining its moisture balance.
In this coconut oil bath bomb, I’ve also added shea butter and coconut oil, two ingredients known for their deep moisturizing and skin-softening properties. The result? Skin that feels truly pampered, even after you’ve stepped out of the tub!
The Role of Starch and SCI
Starch is a common bath bomb filler. I love using rice starch for its extra-soft feel, but cornstarch is an excellent and more accessible option, so feel free to use it as well. In bath products, starch acts as a skin soother, helping to soften water.
To help oils and butters disperse properly in the water, I used a powdered surfactant: Sodium Cocoyl Isethionate (SCI). It’s a mild surfactant that prevents oils from floating on the surface or sticking to the tub. I’ve tried stronger surfactants like SCS in the past, but they often stripped away the nourishing oils. SCI, on the other hand, is gentle and conditioning: one of my favorites, especially for sensitive skin and scalp. It’s a must have in my solid shampoos recipes!
Let’s Talk About the Fizz
Many DIY bath bomb recipes online use a 2:1 ratio of baking soda to citric acid. While that’s effective, in this case I used a more balanced 1.3:1 ratio (1.3 parts of baking soda to 1 part of citric acid). This ratio aligns more closely with the actual stoichiometry of the acid-base reaction and helps create a slower, longer-lasting fizz. Some people like to adjust the ratio depending on their fizzing preferences, it’s all about finding the balance that feels best for your own bath ritual.
A Fragrance That Feels Like a Hug
For this milk bath bomb, I chose Douceur Lactée natural fragrance from Aroma-Zone, a sweet, milky scent that reminds me of sugar, milk and vanilla. It's comforting and dreamy, perfect for this recipe. If you can’t find this fragrance, a soft vanilla note would be a wonderful substitute. Always choose a scent that calms and delights you, fragrance is such an important part of the ritual! 
How to Make a Bath Bomb: My Nourishing Milky Recipe
Ingredients
- Baking soda: 39 g (39%)
- Citric acid: 30 g (30%)
- Powdered milk: 10 g (10%)
- Starch: 9.2 g (9.2%)
- Shea butter: 5 g (5%)
- Coconut oil: 5 g (5%)
- Sodium Cocoyl Isethionate (SCI): 1.5 g (1.5%)
- Fragrance (Douceur Lactée or your choice): 0.3 g (0.3%)
Instructions
- Mix the powders: In a bowl, combine baking soda, citric acid, powdered milk, starch and SCI.
- Melt the butters and oils: Gently melt the shea butter and coconut oil in a water bath.
- Blend it all together: Once melted, add the oils to the powders along with the fragrance. Stir well to create a uniform texture.
- Adjust consistency: Lightly spray witch hazel or alcohol (I prefer alcohol to avoid premature fizzing) while mixing until the blend holds its shape when pressed but isn’t too wet.
- Mold: Pack the mixture into your favorite bath bomb molds.
- Unmold and cure: Let the bath bombs sit for 2–3 days in a dry place before using.
These bath bombs are best enjoyed on quiet evenings when your body asks for softness and your spirit craves a little magic. They make a thoughtful handmade gift too: ust wrap them in tissue paper and a ribbon for a lovely surprise!