It's one of the most common questions we get: "Does your soap contain lye? Is it safe?"
The short answer: yes, lye is used to make our soap. And no, there is no lye left in the finished bar. Those two things are both true, and understanding why will change how you think about soap forever.
First: What Is Lye??
Lye is sodium hydroxide (NaOH) — a highly alkaline substance that, on its own, is caustic and not something you want on your skin. It's the same stuff used to unclog drains. So why on earth is it in soap?
Because without it, you don't have soap. You just have a jar of oil.
The Chemistry (Don't Worry, It's Actually Cool)
When lye is combined with oils or fats, a chemical reaction called saponification occurs. The lye and the oils react completely with each other and transform into two new things: soap and glycerin.
Neither of those things is lye. The lye is gone — consumed entirely by the reaction. What's left is a gentle, skin-loving bar of soap with natural glycerin that moisturizes as you wash.
This isn't a loophole or a technicality. It's basic chemistry. Every bar of real soap — whether it's handcrafted by a small BC maker or mass-produced in a factory — was made with lye. There is no other way to make soap.
"But the Label Doesn't Say Lye..."
You're right — and here's why. Cosmetic labelling regulations require ingredients to be listed as they exist in the finished product, not as they were added during manufacturing. Since there's no lye left after saponification, it doesn't appear on the label.
Instead, you'll see ingredients like saponified coconut oil or saponified olive oil. That "saponified" prefix literally means "reacted with lye." It's the same thing — just listed accurately.
So Is Handmade Soap Safe?
Absolutely — when it's made correctly. A properly formulated cold-press soap is made with a precise lye-to-oil ratio that ensures complete saponification. Reputable soap makers (like us) also formulate with a small "superfat" — a slight excess of oils — which means there's a buffer of unreacted oil left in the bar for extra skin conditioning. This makes it virtually impossible for any lye to remain.
The result is a bar that's gentle, moisturizing, and completely safe for daily use — even for sensitive skin.
What About "Lye-Free" Soap?
If you see a product marketed as "lye-free soap," one of two things is true:
- It's not actually soap — it's a detergent bar made with synthetic surfactants (which is fine, but it's not soap)
- The lye was used in manufacturing but isn't listed on the label (which, as we explained, is completely normal and accurate)
There is no such thing as soap made without lye. Anyone claiming otherwise is either confused or being misleading.
The Bottom Line
Lye makes soap possible. Saponification makes lye disappear. The bar you hold in your hand contains zero lye — just the beautiful, skin-nourishing result of a chemical reaction that humans have been using for thousands of years.
At Pacific Coast Soap Works, we use lye carefully, precisely, and with a healthy respect for the chemistry involved. Every batch is formulated to ensure complete saponification, so you get a bar that's safe, gentle, and genuinely good for your skin.
Curious about what else goes into our bars? Browse our full range of handcrafted soaps — every ingredient is listed right on the product page.
Are you a soap maker looking to source high-quality sodium hydroxide? Check out our Bulk Lye (Sodium Hydroxide) – 25kg — the same food-grade lye we trust in our own cold-press batches.