How to Wash Cast Iron in Dishwasher — Should You

Should You Put Cast Iron in the Dishwasher?

No — never put cast iron in the dishwasher. This is one of the most damaging things you can do to cast iron cookware, and the damage is difficult or impossible to fully reverse. Here is why, and what to do instead.

Why Cast Iron Should Never Go in the Dishwasher

1. It Destroys the Seasoning

Cast iron cookware relies on a layer of polymerized oil called seasoning — built up over time through cooking and proper care — to create a natural non-stick surface and protect the iron from rust. Dishwasher detergent is highly alkaline and strips this seasoning completely in a single cycle.

2. It Causes Rust

Once the seasoning is stripped, bare cast iron is exposed to water and heat inside the dishwasher. Cast iron rusts rapidly when wet. After a dishwasher cycle, rust can begin forming within hours.

3. The Heat Cycle Accelerates Damage

The combination of hot water, harsh detergent, and the heated drying cycle is particularly destructive to cast iron. Even a single dishwasher cycle can undo years of carefully built seasoning.

How to Clean Cast Iron Correctly

For Everyday Cleaning

1. While the pan is still warm (not hot), rinse it under warm running water
2. Use a stiff brush or chainmail scrubber to remove food residue — avoid steel wool which scratches the surface
3. A small amount of mild dish soap is acceptable for occasional use — the idea that soap always ruins cast iron is a myth, but avoid soaking or heavy soap use
4. Rinse thoroughly and dry immediately and completely with a clean cloth or paper towel
5. Place the pan on the stovetop over low heat for 1 to 2 minutes to evaporate any remaining moisture

Re-Seasoning After Cleaning

1. While the pan is still warm from drying, apply a very thin layer of neutral oil (flaxseed, vegetable, or shortening) to the entire surface including the exterior and handle
2. Wipe off the excess with a clean cloth — the layer should be barely visible
3. Store in a dry location

What to Do If Cast Iron Goes in the Dishwasher by Mistake

1. Dry the pan immediately and completely — do not let it sit wet
2. Place it on the stovetop over medium heat to drive out all moisture
3. Apply a thin layer of oil while still warm
4. Re-season in the oven: apply a thin coat of oil, place upside down in a 450°F (230°C) oven for one hour, then let cool in the oven
5. Repeat the oven seasoning process two to three times to rebuild the protective layer
6. If rust has already formed, scrub with steel wool to remove the rust, then re-season from scratch

The Simple Rule for Cast Iron

Cast iron is hand wash only — always. Treat it well and it will last for generations. Put it in the dishwasher and you will spend hours trying to restore it.

Final Tips

• Never put cast iron in the dishwasher — not even once
• Dry immediately and completely after every wash
• Apply a thin layer of oil after drying to maintain the seasoning
• Re-season in the oven periodically to keep the surface in top condition