Can You Use Soap on Cast Iron? Debunking the Old-School Myths

A commonly debated topic in the cast iron community is whether or not it’s safe to clean your pans with soap and water. Some folks believe that letting soap touch a skillet might ruin family traditions — or summon Grandma’s ghost. Others are totally fine with it and see no harm. So where do we stand?

We believe YES — you absolutely can use soap and water. Cleanliness does not ruin cast iron seasoning if you’re caring for your cookware properly. Now that you have the answer upfront, let’s break down why this myth exists, and why it needs to go.

Myth 1: “Soap Contains Lye — and Lye Destroys Seasoning”

This is one of those classic “yes and no” statements.

Soap is created through a process called saponification, where oils are mixed with an alkali like lye. But once saponification happens, the lye is neutralized — it no longer exists in its raw form. That’s why soap doesn’t burn your skin when you wash your hands with it.

It’s true that pure lye can strip seasoning — we use lye baths to clean iron during restoration. But the lye used in modern soap is long gone by the time you’re cleaning your skillet. So no — a little dish soap will not destroy your hard-earned seasoning.

Myth 2: “My Grandmother Would Kill Me If I Used Soap”

We doubt Grandma Clara Bell would be thrilled about a dirty pan hanging on the wall, either.

The belief that soap ruins cast iron probably comes from older generations who seasoned with animal fats like lard or bacon grease. When not cleaned properly, those can go rancid. But that doesn’t mean they skipped cleaning entirely. Soap helps remove food and oils — it doesn’t remove seasoning.

What seasoning isn’t: a layer of old bacon grease that’s never washed off.
What seasoning is: a thin, polymerized layer of oil that’s bonded to the metal after high-heat application.

Once your skillet is seasoned properly, a gentle clean with soap and water will not undo it. If your seasoning comes off with a quick wash, it likely wasn’t bonded well to begin with.

So... Can You Use Soap on Cast Iron?

Yes, yes, and yes again.

Modern dish soap will not ruin your pan. What will ruin your pan is leaving it wet, letting food sit too long, or storing it with a layer of oil slathered on like it’s headed to a bodybuilding competition.

Here’s how we recommend cleaning your cast iron:

• Clean it while still warm using soap, water, and a gentle scrub pad or chainmail.
• Dry thoroughly — wipe it down, then warm it in the oven for a few minutes to evaporate moisture.
• Lightly oil it with a paper towel (emphasis on lightly) to restore sheen without buildup.

Proper care will deepen your seasoning, not strip it. So don’t fear the soap — just respect the process.

Enjoy the cook!
– C&CB