How to Remove Grease From Concrete: 5 Methods That Work
Grease on concrete is one of those problems that looks permanent but usually isn't. The key is matching the method to the severity of the stain. A fresh spot needs a different approach than a stain that's been there since the previous owner of the property.
Here are five methods in order from lightest to heaviest.
Method 1: Kitty Litter (For Fresh Spills)
If you're dealing with fresh oil or grease — still wet, spilled in the last hour or two — the first step isn't a cleaner. It's an absorber.
Pour a generous layer of kitty litter (clumping or non-clumping), baking soda, or cornmeal over the spill. These materials draw the free oil up and out of the surface pores. Leave for 20–30 minutes, then sweep up.
This won't remove everything, but it removes a significant portion of the fresh oil and makes the subsequent cleaning step easier. Fresh spills treated this way are much easier to fully remove than spills that were left to soak unassisted.
Method 2: Dish Soap and Scrubbing (Light Stains)
For light, recent stains on sealed or relatively non-porous concrete, dish soap is surprisingly effective. Dawn or similar degreasing dish soaps contain surfactants that work on cooking and light mechanical oils.
Apply concentrated dish soap directly to the stain, add a little hot water, and scrub with a stiff brush. Rinse and repeat.
This is best for light staining and fresh deposits on sealed concrete. For anything soaked into bare concrete or more than a few weeks old, dish soap typically falls short.
Method 3: Biodegradable Degreaser (Moderate Stains)
For oil and grease stains that have had time to soak in — a week to several months old — a dedicated degreaser is the right tool. It has enough surfactant concentration and chemistry to penetrate the concrete pores and emulsify the embedded oil.
Mad Degreaser handles moderate concrete staining well. Apply, let it dwell for 5–10 minutes, scrub with a stiff brush, and rinse. Repeat if needed.
Low-odour and biodegradable, this is a practical choice for an enclosed garage where you don't want strong chemical fumes.
Method 4: Heavy-Duty Degreaser (Old or Severe Stains)
Old, dark, set-in stains — the kind from a vehicle that dripped for years in the same spot — need more power. This is where AB-50 Degreaser comes in.
Apply AB-50 at full or near-full strength directly to the stain. Allow it to dwell for 10–15 minutes. Scrub aggressively with a stiff concrete brush. Rinse. Inspect. Repeat.
Deep stains may not come 100% clean on the first pass. But they should visibly improve, and a second or third treatment usually reduces the stain to a significantly faded version if not full removal.
The combination of a strong degreaser + hot water rinse + pressure (from a pressure washer if available) is the most effective approach for severe staining.
Method 5: Cat Litter Poultice (For Deep, Old Stains)
For very deep, old stains where direct application of degreaser and scrubbing hasn't fully worked, a poultice approach can help draw embedded oil out of deeper pores.
Mix an absorbent material (cat litter powder, pool absorbent, or sawdust) with degreaser to create a thick paste. Apply the paste over the stain in a layer approximately 1/4 inch thick. Cover with plastic sheeting and tape the edges to slow drying. Leave for 24–48 hours.
As the paste dries, it draws oil up from the concrete pores into the paste through a wicking action. When you scrape it off, the oil comes with it. Rinse and inspect. This is a slow method but often works on stains that don't respond to direct application.
Practical Notes on Concrete Cleaning
Hot water helps: Warm or hot water activates degreaser more effectively than cold water.
Don't let degreaser dry: If it dries on the surface before you rinse, it leaves residue. Keep it active with a mist of water if needed.
Sealed concrete is much easier to clean: If you're doing a major floor clean, consider sealing afterward.
Old stains may not fully disappear: Very old, severe staining that has had years to soak deep into unsealed concrete may lighten significantly but may not fully disappear. Manage expectations accordingly — even 70% improvement on an old stain is meaningful.
For the degreasers mentioned above — Mad Degreaser and AB-50 Degreaser — visit themadchemisthomesupply.com. Both are made in Alberta, biodegradable, and designed for exactly this type of work.