Grease and oil stains, cooking oil, butter, salad dressing, food grease, are not water-soluble, which is why dabbing them with water or plain soapy water does almost nothing and can spread them. The method is to remove and absorb the excess first, then break the oil down with a degreaser, a little clear dishwashing liquid solution or a dry-cleaning solvent, rather than flooding the area with water. On upholstery you must first check the fabric cleaning code, because some fabrics only tolerate solvent and not water. Fresh grease usually lifts well with patience; old, set-in or large oily stains, and oily soil on polypropylene carpet, often need professional treatment.
Why grease and oil resist water
Oil and water do not mix, so water-based cleaning cannot dissolve an oily stain, it just sits on top of it. To remove grease you need something that can break it down: a surfactant such as dishwashing liquid, which is designed to emulsify oil so it can be rinsed, or a solvent that dissolves it directly. This is the same chemistry behind why grease re-soils a carpet so quickly, the oily film grabs dry dirt, see why carpets re-soil quickly.
Step 1: remove and absorb the excess
Lift off any solid or thick grease with the edge of a spoon, scraping toward the centre so you do not spread it. Then absorb the oil that has soaked in: sprinkle a generous layer of bicarbonate of soda or cornflour over the stain, press it in gently, and leave it for at least 15 minutes, longer for a heavy stain, so it can draw the oil out of the fibre. Vacuum it up thoroughly. Repeat the absorption step if the powder turns greasy, the more oil you remove dry, the easier the next stage.
Step 2: degrease
Mix a few drops of clear, mild dishwashing liquid into warm water, dampen a white cloth, and dab the stain from the outside inwards, turning to a clean section as the grease transfers. For a stubborn oily stain a dry-cleaning solvent on a cloth works directly on the oil, test it on a hidden area first. Blot, then rinse by blotting with a cloth dampened in clean water, and dry. Avoid soaking the carpet; the work is done by the degreaser, not by volume of water.
Cooking oil and food grease on upholstery
On a sofa or chair, check the cleaning code before you do anything, see the W, S, WS and X fabric codes explained. A "W" fabric can take the water-based dishwashing-liquid method; an "S" fabric is solvent-only and must not be treated with water, so it needs a dry solvent; "WS" allows either; and "X" should be vacuumed only and left to a professional. The absorb-with-powder first step is safe on all of them and worth doing before any cleaning. We clean fabric and microfibre upholstery, not leather or genuine suede.
Polypropylene carpet and oily soil
Polypropylene, also called olefin, is a common synthetic carpet fibre that is oil-loving by nature, so oily stains and oily traffic-lane soil cling to it stubbornly and re-appear easily. You can still treat individual grease stains with the method above, but olefin carpet that has gone grey and greasy across the traffic lanes usually needs professional solvent-side treatment and controlled extraction to lift the oily film, see grease and protein stains.
What not to do
- Do not start with water. Water spreads oil without dissolving it; absorb and degrease first.
- Do not rub. Rubbing pushes grease deeper and can distort the pile.
- Do not use water on an "S" or "X" coded fabric. Check the code first.
- Do not skip the spot test before using any solvent.
When to call a professional
If the stain is large, old, has set in, is on an "S" or "X" fabric or on wool, or if the oily soil covers whole traffic lanes, professional treatment is the safer route. A professional has the degreasers and controlled extraction to lift oily soil without over-wetting or damaging the fibre, see removing set-in stains.
Common questions
How do you get grease and oil out of carpet?
Scrape off the excess, then absorb the soaked-in oil with bicarbonate of soda or cornflour, leave it 15 minutes and vacuum. Next, dab with a mild dishwashing-liquid solution, or a dry-cleaning solvent for stubborn grease, working from the outside in, then blot, rinse lightly and dry. Grease is not water-soluble, so absorbing and degreasing does the work, not water.
Does bicarbonate of soda remove oil stains from carpet?
It does not clean the stain, but it is excellent at the first step, absorbing oil out of the fibre so there is less to clean. Sprinkle it on, press it in, leave it at least 15 minutes and vacuum, repeating if it turns greasy. You then degrease the remaining mark with a dishwashing-liquid solution or solvent.
Can old grease stains be removed from carpet?
Fresh grease usually lifts well, but old, set-in oily stains are much harder because the oil has bonded to the fibre and attracted dry soil over time, especially on oil-loving polypropylene carpet. These often need professional degreasers and controlled extraction to remove safely without over-wetting the carpet.
For grease and oily stains that will not lift at home, see our carpet cleaning and upholstery cleaning services, or request a free quote.