Difference Between Castile and Bastille Soap: A Personal Perspective.

byrontobroome
Nov 15
2 min read

When it comes to handmade soap, two names often come up: Castile and Bastille. Both are rooted in tradition, both are olive-oil rich, and both are wonderfully gentle on the skin. But the difference between Castile and Bastille soap comes down to personal reasons and the way each one feels when lathered.

🌿 What is Castile Soap?

True Castile soap is made with 100% olive oil, water, and lye - that's it!
The lather is unique: creamy, lotion-like, and silky rather than bubbly.
Because it is made with pure olive oil, Castile soap is considered one of the most conditioning soaps available. It’s especially loved by those with sensitive skin, babies, or anyone who prefers a mild, nourishing cleanse.

🌸 What is Bastille Soap?

Bastille soap is similar but includes other oils alongside olive oil. To qualify as Bastille, it must contain at least 70–75% olive oil.
My own Bastille recipe is over 80% olive oil, with just coconut oil and castor oil added. These additions give the soap a little more cleansing power and a touch of bubbly lather, while still keeping it gentle and conditioning.
The result is a bar that feels close to Castile but with a livelier lather and slightly firmer texture.

✨ Lather Difference between Castile and Bastille Soap

The difference between Castile and Bastille soap is most noticeable in the lather.

Castile soap: lotion-like, creamy, and soft.
Bastille soap: still creamy but with a hint of bubbles thanks to coconut and castor oil.

Both are unfragranced, which makes them suitable for all skin types, including sensitive, dry, or easily irritated skin.

🌍 Health & Skin Benefits

Gentle cleansing: Both Castile and Bastille are free of synthetic detergents and fragrances, making them hypoallergenic and safe for sensitive skin.
Moisturizing: Olive oil is rich in antioxidants and fatty acids that help nourish and protect the skin.
Suitable for all skin types: Their mildness makes them ideal for everyone, from babies to adults, and for conditions like eczema or dryness.

💚 Why I Make Both

For me, it’s about balance. Castile soap offers that luxurious, lotion-like lather that feels like a skin treatment. Bastille soap, with its added oils, gives a little more cleansing power and a touch of bubbly joy. Both are humble, handmade, and crafted with care - amazing for all skin types and a beautiful reminder that simplicity often works best.

✨In short, the difference between Castile and Bastille soap is subtle but meaningful. Castile is pure olive oil with a silky lather, while Bastille blends olive oil with other oils for a bubblier, firmer bar. Both are gentle, nourishing, and unfragranced - perfect for anyone seeking a natural, skin-friendly soap.