The Best Oil to Season Cast Iron (And What to Actually Avoid)

Seasoning cast iron means baking a thin layer of oil into the surface until it polymerizes — forming a hard, slick, rust-resistant coating. The right oil makes that coating durable and even. The wrong oil leaves a sticky, blotchy mess you’ll have to sand off.

The short answer: avocado oil or grapeseed oil are the best choices for most people. Canola works fine too. Here’s why, and what to skip.

What Makes an Oil Good for Cast Iron Seasoning

Two properties matter:

High smoke point. Seasoning happens at oven temperatures of 400–500°F. The oil needs to handle that heat without burning before it polymerizes. Oils with low smoke points smoke and burn instead of bonding, leaving a sticky residue.

Drying tendency. Some oils polymerize (harden) better than others when heated. Oils higher in polyunsaturated fats tend to polymerize more completely and create a harder, more durable seasoning layer.

Best Oils for Seasoning Cast Iron

Avocado Oil — Best All-Around

Smoke point around 500°F, neutral flavor, widely available. Polymerizes well and produces a hard, durable seasoning layer. Works at any oven temperature used for seasoning without burning. The best choice for most people seasoning cast iron.

Chosen Foods 100% Pure Avocado Oil is the most commonly recommended brand.

Grapeseed Oil — Runner-Up

Smoke point around 420°F, very neutral flavor, high in polyunsaturated fats that polymerize well. Produces a good seasoning layer and is relatively affordable. A solid second choice.

Canola Oil — Reliable Everyday Option

Smoke point around 400°F. Not as high as avocado or grapeseed, but still within the range for oven seasoning at 400–450°F. Produces a good seasoning layer and is the most affordable option. Works well for regular maintenance seasoning coats.

Crisco / Vegetable Shortening

The traditional recommendation for cast iron seasoning. Works reliably — many cast iron pans have excellent seasoning built entirely on Crisco. Lower smoke point than avocado oil, but at a thin enough coat it seasonings fine at 400–450°F.

What to Skip

Olive oil: Smoke point too low (375°F extra virgin, 468°F light). Extra virgin especially burns before polymerizing and leaves a rancid-smelling residue. Skip it for seasoning — it’s fine for cooking in cast iron once seasoned.

Butter: Milk solids burn and leave a sticky, brownish residue rather than a clean seasoning layer. Not for seasoning, though it’s great for cooking.

Unrefined coconut oil: Smoke point of 350°F — too low. Refined coconut oil (450°F) can work but offers no advantage over cheaper options.

Flaxseed oil: Once heavily promoted as the “ideal” cast iron seasoning oil due to its high linolenic acid content. In practice, flaxseed-seasoned pans tend to flake and chip over time. Not recommended.

How to Season Cast Iron in the Oven

This process works for a first seasoning or restoring a stripped pan.

Wash the pan with hot water and a small amount of dish soap to remove any manufacturing residue or old rancid oil. Rinse thoroughly.
Dry completely. Put the pan on the stovetop over low heat for a few minutes to evaporate all moisture — any remaining water will cause rust during the oven step.
Preheat your oven to 450–500°F.
Apply a very thin layer of oil to every surface — inside, outside, handle. Use a paper towel to rub it in, then use a clean dry paper towel to wipe off as much as possible. The layer should look almost dry. Too much oil pools and creates a sticky, uneven coating.
Place pan upside down on the middle oven rack. Put a sheet of foil on the rack below to catch any drips.
Bake for one hour. The oil will smoke — this is normal.
Let the pan cool completely in the oven before removing. Don’t rush this step.

Repeat 2–4 times for a new pan to build up a good base layer. Each subsequent coat adds depth and improves non-stick performance.

Maintenance Seasoning After Each Use

You don’t need to do a full oven session after every cook. For regular maintenance:

After cleaning, dry the pan completely on the stovetop over low heat
While still warm, apply a very thin wipe of oil with a paper towel — just enough to leave a faint sheen, not a visible coat
Wipe off the excess

This is the same oil-after-every-use habit that applies to outdoor Blackstone griddle seasoning — see the Blackstone seasoning guide for that process. The principle is identical: thin coat, heat to bond, done.

Frequently Asked Questions

What is the best oil for seasoning cast iron? Avocado oil is the best all-around choice — high smoke point (500°F), neutral flavor, polymerizes into a hard durable layer. Grapeseed oil is a close second. Canola works fine and is the most affordable option.

Is olive oil good for seasoning cast iron? No. Olive oil’s smoke point is too low for oven seasoning temperatures. It burns before polymerizing and can leave a sticky, rancid residue. Use olive oil for cooking in cast iron once it’s already seasoned.

Can I use flaxseed oil to season cast iron? It was popular for a while but has fallen out of favor. Flaxseed-seasoned pans tend to develop a seasoning that flakes and chips over time rather than building a stable, durable layer. Avocado or grapeseed oil produces better results.

How often should I re-season cast iron? A thin maintenance coat after each use keeps the seasoning in good shape. A full oven re-seasoning is only needed if the pan becomes sticky, develops rust, or the seasoning visibly strips — which shouldn’t happen with regular maintenance.

Can I season cast iron on the stovetop instead of the oven? You can do a maintenance wipe on the stovetop, but a full seasoning session is better in the oven. The oven heats the entire pan evenly (including sides and handle) and holds the temperature consistently for the full hour the oil needs to polymerize.

Does the type of cast iron (Lodge, vintage, etc.) change which oil to use? No. The seasoning process and oil choice are the same regardless of brand or age.