Can You Compost Cooking Oil?

Updated

On this page
  1. At a glance
  2. What to do with cooking oil instead
  3. What goes wrong
  4. Worm bins and bokashi
  5. FAQ
No

No. Poured oil and grease coat compost materials, block air and water, go rancid and attract animals. A little dressing on salad scraps is fine, but leftover frying oil belongs in the trash or a cooking-oil drop-off.

At a glance

Home compost pileNo
Green or brownNeither (not a green or brown input)
MoistureWet
PrepNone needed
Worm binNo
BokashiWith care

What to do with cooking oil instead

Wipe greasy pans with a paper towel before washing and trash the towel. Many cities list cooking-oil drop-off points that send it for biodiesel.

Let used oil cool, pour it into a sealable container and put it in the trash, or take larger amounts, like deep-fryer oil, to a cooking-oil or household waste drop-off if your area has one. Never pour it down the drain. Scraps with a light coating of oil can still go in the pile.

What goes wrong

Oil in a pile makes greasy, smelly patches that repel water and slow decomposition. If you poured some in, mix in plenty of dry browns like shredded paper or sawdust to soak it up. Animals will sniff it out, so cover it well.

Worm bins and bokashi

Worm bin: Keep oil and grease out of worm bins; it coats the bedding and can harm the worms.

Bokashi: Small amounts of oil on food scraps are fine in bokashi, but don't pour in liquid oil.

Balancing the rest of your pile? Check the balance with the compost mix calculator.

Frequently asked questions

Can you compost vegetable oil?

Not in any quantity. A little on food scraps is fine, but poured oil coats materials and slows decomposition.

Can you compost paper towels with grease on them?

A few lightly greasy paper towels are fine buried in an active pile. Towels soaked in oil or meat fat belong in the trash.

Where can I dispose of used cooking oil?

Many cities and some recycling centers accept used cooking oil. Otherwise, seal it in a container and put it in the trash.