Guides
How to fix a rusty cast iron pan
The short answer: scrub the rust off with steel wool, wash the pan, dry it on the hob, wipe on a very thin coat of oil and bake it upside down at 230°C for an hour. Repeat the oil and bake two or three times and it is ready to cook with. Rust on bare cast iron is almost never the end of a pan.
First: is it bare or enamelled?
This method is for bare cast iron: black pans with no glaze, like a cast iron frying pan or skillet. Enamelled cast iron has a glass coating and is cleaned differently; never take steel wool to it. If an enamelled casserole shows rust, it will be on an unglazed rim, and drying it well and wiping it with a little oil is all it needs. See how to clean an enamelled cast iron casserole.
How to restore a rusty pan, step by step
Scrub. Use steel wool with a little water and a drop of washing-up liquid. Work until the orange is gone and you see grey or dark metal. Do the base, sides and handle too.
Wash and rinse in hot water to take away the loose rust.
Dry on the heat. Towel it off, then put it on the hob over a medium heat for 5 minutes until every trace of moisture has gone. Bare iron rusts again within minutes if it is left wet.
Oil very thinly. While it is warm, rub in a teaspoon of a high smoke point oil such as sunflower, rapeseed or vegetable oil, everywhere, inside and out. Then take a clean cloth and wipe it all off as if you had used too much. What remains is the right amount.
Bake upside down. Heat the oven to 230°C, put a tray of foil on the lower shelf to catch drips, and put the pan upside down on the shelf above for 1 hour.
Cool in the oven. Turn the oven off and leave the pan inside until it is cool enough to handle.
Repeat. Do steps 4 to 6 two or three times. Each layer of polymerised oil builds a harder, darker, slicker surface.
Why the oil has to be thin
Seasoning is oil that has been heated past its smoke point until it turns into a hard, plastic-like layer bonded to the iron. A thin film does this cleanly. A thick one does not cure all the way through and leaves the pan sticky and patchy. If your pan comes out tacky, it had too much oil: put it back in for another hour, and use less next time.
How bad is too bad?
| What you see | What to do |
|---|---|
| Light orange spots or film | Scrub, dry, oil, one bake. Twenty minutes of work. |
| Rust across the whole surface | The full method above, with two or three bakes |
| Thick, flaking rust | Soak in equal parts white vinegar and water for up to 1 hour, checking every 15 minutes, then scrub and season. Do not leave it longer: vinegar eats the iron once the rust is gone. |
| A crack right through the iron | The pan cannot be repaired |
How to stop it rusting again
- Dry it on the heat after every wash, not just with a tea towel.
- While it is still warm, wipe on a few drops of oil.
- Don't leave it to soak, and never put it in the dishwasher.
- Store it dry, with a sheet of kitchen paper inside if you stack pans.
- Keep long, acidic simmers such as tomato sauce for an enamelled pot.
- Cook with it often. Every fry adds to the seasoning.
The Season Cast Iron Frying Pan
Our Cast Iron Frying Pan is bare cast iron, pre-seasoned at the factory (dipped in oil and baked), so it is ready to use straight out of the box. It works on all hobs including induction, and in the oven, under the grill or over a barbecue. Metal, wooden and silicone utensils are all fine, and it has pouring spouts on both sides. It is not dishwasher safe: wash by hand in warm water and dry it on the heat, as above. It comes in 10, 16, 20, 25 and 30cm, from £12 to £38. If yours ever rusts, this is the method that brings it back.
Keep reading
- How to season your cast iron frying pan
- Do I need a cast iron frying pan?
- Enamelled or bare cast iron: which should I buy?
- How to use a griddle pan
Questions people ask
Can I cook in a pan with a little rust? Scrub it off first. Rust makes food stick and tastes of metal, and it takes five minutes to remove.
Can I use washing-up liquid on cast iron? Yes, a little is fine on a seasoned pan. Modern washing-up liquid does not strip baked-on seasoning; soaking and the dishwasher do the damage.
Which oil is best for seasoning? Any neutral oil with a high smoke point: sunflower, rapeseed or vegetable oil. Avoid butter and olive oil for this job.
Why is my pan sticky after seasoning? Too much oil. Bake it for another hour at 230°C, and wipe the next coat thinner.
Does enamelled cast iron rust? The enamel does not. Any bare edge, usually the rim, can, and drying it well is the fix.
Cook it with
Cook like it matters.
From the cooks at Season, a London cookshop since 2005.