Grease is the exception to almost every rule on this site. The universal advice — blot, cold water, work inward — is wrong here, and following it makes the mark bigger.
Why water is the wrong first move
Oil and water do not mix. Adding water to an oil stain cannot lift it out of the fibre; it simply carries the oil outward into clean pile and turns a 5cm mark into a 15cm one.
Oil has to be absorbed or dissolved, not diluted.
The powder method
This is the whole technique
Cover the stain generously with a dry absorbent powder. Leave it for several hours or overnight. Vacuum it away. Repeat until no more oil transfers. Patience does most of the work here — the powder is drawing oil out by capillary action, and that takes time.
- Blot away any surface oil with a dry cloth. No water.
- Cover generously with cornflour, bicarbonate of soda or talc — a thick layer, not a dusting.
- Leave several hours, or overnight for anything substantial.
- Vacuum thoroughly, with suction.
- Repeat. Two or three cycles is normal on a fresh stain, more on an old one.
Only once the powder stops picking up oil should you consider anything wet.
After the powder
If a mark remains, then and only then:
On wool — a drop of wool-safe detergent (pH 5–7) in cold water, applied to a cloth rather than to the rug, blotted, then blotted again with plain water to rinse. Never dish soap, which is alkaline — see cleaning wool rugs.
On synthetics — dish soap is fine and cuts grease well. Polypropylene tolerates it, and can often be hosed down outdoors.
Solvents — dry-cleaning solvent works on oil but strips dye, softens latex backings and is a professional's tool. Not a domestic one.
Why oil is worse on some fibres
| Fibre | Behaviour with oil |
|---|---|
| Wool | Lanolin resists water, not oil. Oil penetrates readily. |
| Polyester | Worst. Oleophilic — actively attracts and holds oily soil. |
| Polypropylene | Good. Repels most things including oil. |
| Nylon | Moderate; treated versions resist well |
| Cotton | Absorbs readily; but often machine washable |
| Jute / sisal | Absorbs instantly, and water cleaning watermarks |
| Viscose | Do not attempt. Any moisture marks it. |
Polyester deserves the note: it is oleophilic, meaning it chemically attracts oily soil. That is why polyester rugs develop grey traffic paths that cleaning never quite lifts — the soil is oil-bound, and it is in the fibre rather than on it.
Where grease actually comes from
Mostly kitchens, and not as spills. Cooking aerosolises fat, which settles across the room and works into pile over months. By the time it is visible it is everywhere rather than in one spot, and it is a wash rather than a spot-treatment job.
That is the main argument for keeping wool out of a kitchen and using something washable or synthetic instead.
When to go professional
Large areas. Anything on silk, viscose or an antique. Motor oil or anything with pigment in it as well as oil. And accumulated cooking grease across a whole rug, which needs immersion washing rather than spot work — DIY vs professional.
General method for other spills in rug stains.
Common questions
Why doesn't water work on a grease stain?
Oil and water do not mix, so water cannot lift oil out of a fibre — it just spreads the area and pushes the oil outward into clean pile. Grease has to be absorbed with a dry powder or dissolved with a solvent, not diluted.
Does dish soap work on rug grease?
It cuts grease well, which is why it is tempting, but most dish soaps are alkaline and alkali damages wool — it strips lanolin and leaves the fibre dull and brittle. On wool use a wool-safe detergent instead; on synthetics dish soap is fine.