When you dispose of cooking oil do normally you toss it out, reuse it, or recycle it? Learning how to get rid of used cooking oil can be challenging. How you choose to get rid of it will impact the environment and can potentially damage your pipes. 

Three Ways To Dispose of Cooking Oil

1. Throw The Oil Away

I rarely save cooking oil. I feel the oil has served its purpose after one use. However, if you are like me and decide to toss it out, here is an easy way to do it:

  • Allow the oil to cool first. You can let it stand overnight or place it in the freezer after it has reached room temperature.
  • Pour or scoop the used oil in an un-breakable container that can be resealed. Take-out containers (or used water bottles with lids) work well. Just snap the lid on and seal the rim with tape to keep it closed. Toss it in the trash can.
  • Freeze the oil, then you can place it in a heavy-duty garbage bag. It is better if the bag is filled with paper towels, veggies or other absorbent trash.
  • Toss the used oil into your garbage can with care. Rodents and other vermin will be attracted to the smell.

items needed for proper disposal of used kitchen grease

used grease is poured into container for disposal

used grease container is taped around edges to prevent spillage

2. Re-use The Oil

Decide if the oil can be reused. If the oil is dark and has bits of meat in it, then maybe you should just toss it out. If the oil is clear, then you’re probably good-to-go.

Try to remember the type of food that was cooked in the oil. You don’t want to fry your sopapillas in oil that was used for frying fish.

Here are some basic guidelines to follow:

  • Wait until the oil cools.
  • Filter out the floating food particles with a coffee filter.
  • Pour the used oil into a resealable container.
  • Store your filtered oil at room temperature.
  • Do not re-use more than twice.

3. Recycle The Oil

Recycling is always a good idea. A quick internet search should help you find a municipal or commercial recycling facility close to you. Pay attention to the instructions on how to package the oil to be recycled. Your local fire department can also help you find a place to take your used oil.

Another way to recycle used cooking oil is to use it as a way to zap weeds. This technique is environmentally safe and shouldn’t damage your lawn’s ecosystem. However, this method of recycling does not apply to fossil fuel-based oils.

grass growing in concrete

Photo by Tambira Photography

How Not To Dispose Of Your Cooking Oil

Never, ever, pour cooking oil down the drain.

Despite your best efforts, some oil will escape in the dishwater during cleanup. Here are a couple of steps you can take to minimize the impact:

  1. Wipe pots and pans with a paper towel before placing them in the sink or dishwasher.
  2. Use sink strainers to catch waste while you’re doing food prep.

You should also pay attention to what you allow to pass through the garbage disposal. For instance, hard to grind food and fibrous vegetables clog pipes and trap grease.

(HowTo with GEO YouTube Channel)

Try This Before You Call A Plumber

No matter what you do there will be spillage. Here are 3 ways you can try to clear the clog before you call a plumber.

  1. Try using a plunger to loosen trapped food and grease.
  2. Pour boiling water mixed with salt down the drain.
  3. Use a plunger to unstop the clog.

Be sure to use the right plunger for the job. In the illustration below, the smaller red plunger is designed for kitchen sinks. The large black one is designed for toilet clogs.

kitchen and bathroom plungers

What Happens In The Sewer System

When dishwater enters the drain it travels through a system of pipes. The drain pipes from your home connect to a larger city sewer ‘main’ line. Then, the wastewater is routed to a treatment facility. Discarded materials like baby wipes, toys, or feminine hygiene products are removed.

graphic illustration of municipal water and sewer system

(Graphic by Troy McQuillen via dakotafire.net – Click to Enlarge)

Next, the leftover wastewater will go through an aeration process. Bacteria will break down what’s left.

Oily scum and residues are removed during the next phase of the treatment process. Primary and secondary treatment phases involve sludge digestion and a drying process.

The treated water can be either re-claimed or discharged into holding ponds, before being released into a large body of water (like an ocean). Leftover dried sludge is disposed of or reused. Most gases are burned off or used as energy for the treatment plant.

What Could Possibly Go Wrong?

In the early phase of the wastewater journey through the sewer system, the oil will be suspended in dishwashing detergent. However, the oil gets diluted, it begins to coagulate. The fat blobs will then attach to the walls of the pipes. Any bends or obstruction in the pipes will exacerbate the buildups so they grow into what is known as Fatbergs. 

They are the Loch Ness monsters of the sewer system universe and we all play a part in creating them. How?  Every time we allow grease to escape into the kitchen sink or garbage disposal, we’re creating Fatbergs in the sewer system.


(Hydro Cleansing YouTube Channel)

The United Kingdom and the United States hold the record for creating the most Fatbergs. These foul and expensive floating grease and waste obstructions cost taxpayers hundreds of thousands of dollars each year to eradicate.

The proper disposal of kitchen cooking oil is a responsibility we all share as we strive to become better stewards of the environment.

Related Articles