How to season a cast iron pan

Photo by Wright Brand Bacon on Unsplash

What seasoning is and why it matters

Seasoning is a thin, hard layer formed when oil is heated on cast iron until it bonds to the surface. Done well, it gives you a naturally slick finish that helps food release and protects the metal from rust. You’re not aiming for a greasy coating; the best seasoning is dry to the touch and slightly satin, not shiny and tacky.

You’ll season a brand-new pan before first use, and you’ll top it up from time to time if food starts to stick or you see dull grey patches. A well-seasoned pan can sear steaks, fry eggs and roast vegetables beautifully.

What you’ll need

• Clean, dry cast iron pan (bare cast iron, not enamelled cooking surface)
• Neutral, high-smoke-point oil: rapeseed, sunflower or grapeseed; some cooks use flaxseed
• Kitchen roll or a lint-free cloth
• Oven and a baking tray lined with foil, or do a quick top-up on the hob
• Heatproof gloves or thick oven mitts

Before you start: check and prep the pan

If the pan is new and lightly oiled from the factory, wash it with hot water and a drop of washing-up liquid to remove the protective film, then rinse and dry thoroughly on a low hob heat until all moisture has evaporated.

If the pan is used and has rust or stuck-on residue, scrub it back to bare metal with a non-scratch scouring pad or chainmail scrubber. For stubborn rust, a paste of coarse salt and a little oil can help. Rinse, then dry completely over heat—any lingering water will cause flash rust.

Oven seasoning: the reliable method

1. Heat the oven and position racks

   Preheat to 220–240°C (200–220°C fan). Move a rack to the upper-middle and put a foil-lined tray on a lower rack to catch drips. Allow the oven to fully preheat.

2. Apply a very thin film of oil

   Add a teaspoon or so of oil to the warm, dry pan. Using kitchen roll, rub it over the entire surface—inside, outside and handle—then wipe almost all of it off. You should see a slight sheen, not visible wet patches.

3. Bake the pan upside down

   Place the pan upside down on the upper rack. This prevents pooling. Bake until the oil has darkened and set into a dry layer. Allow roughly an hour for a solid first coat.

4. Cool in the oven

   Turn off the heat and let the pan cool inside the closed oven so the layer hardens gradually. This helps reduce tackiness.

5. Repeat for a stronger base

   For a new or stripped pan, add two to three coats in total: a whisper-thin wipe of oil each time, followed by another bake. Multiple thin coats beat one thick, sticky one.

Quick top-up on the hob

If your pan has a small dull patch or food has started to cling, a quick hob top-up can restore the finish between oven sessions.

1. Warm, then oil lightly

   Heat the pan over medium heat until just warm. Rub in a tiny amount of oil with kitchen roll and wipe off the excess.

2. Heat until the surface looks dry

   Keep the pan over medium-high heat until the thin film just begins to smoke lightly and turns dry and satin, then continue for 2–3 minutes. Ensure good ventilation. Let it cool. Repeat once more if needed.

Care after each use

• Rinse while the pan is warm. Use hot water and a non-scratch brush. A small splash of washing-up liquid is fine if needed.
• For stuck bits, simmer a little water for a minute to loosen, or scrub with coarse salt and a drizzle of oil.
• Dry thoroughly on the hob until there’s no steam.
• Wipe on a few drops of oil while warm, then buff until the surface feels dry—not greasy. This thin conditioning layer keeps rust at bay.

Troubleshooting common issues

Sticky or gummy surface

Too much oil or not enough heat. Scrub the tacky layer with hot water and a non-scratch pad, dry, then apply a whisper-thin coat and bake again.

Flaking seasoning

Often caused by thick coats or using an oil layer that didn’t fully set. Strip the affected area back to smooth metal and rebuild with very thin coats.

Rust spots

Light rust can be scrubbed off, then the area reseasoned. For widespread rust, strip the pan and do a full oven seasoning.

Uneven colour

Normal for a new pan. Colour evens out with use as layers build. Focus on performance—food release—over appearance.

What to cook first

For the first few cooks after a fresh seasoning, choose fatty, forgiving dishes to reinforce the coating: crispy-skinned chicken thighs, bacon, sausages, smashed potatoes or a shallow fry. Avoid long tomato-based sauces or boiling acidic liquids at first, as strong acidity can dull a new layer. Once the seasoning is robust, your pan can handle quick acidic touches without issue.

Mistakes to avoid

• Using too much oil. Thick layers stay sticky and will flake.
• Skipping the wipe-back. Always buff until the pan looks nearly dry before heating.
• Seasoning at low heat. The oil needs enough heat to transform into a hard, dry layer.
• Storing damp. Even a little hidden moisture invites rust.
• Expecting non-stick straight away. Cast iron improves with repeated use and light re-oiling.

Cast iron seasoning: quick answers

Do I need to season an enamelled cast iron pan?

No. Enamelled surfaces don’t need seasoning. Only bare cast iron needs a polymerised oil layer for protection and release.

Can I use olive oil to season?

It’s better to use a neutral, high-heat oil. Extra-virgin olive oil can smoke and stay tacky during seasoning, though it’s fine for cooking.

Is washing-up liquid safe on cast iron?

Used sparingly, yes. A small amount won’t strip a well-bonded seasoning. Rinse and dry thoroughly afterwards.

How often should I reseason?

Only when needed. If food starts sticking or you see bare grey patches or rust, do a top-up or a full oven seasoning.

Why is my pan grey after scrubbing?

You’ve likely removed some seasoning and exposed bare iron. Dry it fully and rebuild with thin oil coats to restore the finish.