How to Remove Scratches from Car Paint: What Polishing Can Fix and What It Can't

Most light scratches and swirl marks sit in the clear coat and can be removed with machine polishing. Run a fingernail gently across the scratch: if your nail doesn't catch, it is usually in the clear coat and polishable. If your nail catches, or you can see a different colour inside the scratch, it has gone deeper and will likely need touch-up paint or a respray.

Car paint is built in layers: a thin clear coat on top, the base coat (the colour) under it, then primer, then the metal or plastic panel. Polishing works by removing a very thin layer of clear coat to level out the scratch. That is why it fixes scratches in the clear coat but cannot fix scratches that have cut into the colour or deeper.

1. Wash and dry the area so dirt doesn't fool you.
2. Run your fingernail gently across the scratch, not along it.
3. Nail glides over: likely a clear coat scratch. Usually polishable.
4. Nail catches slightly: may be borderline. A specialist can measure paint depth before deciding.
5. Nail catches clearly, or you see white, grey or metal: through the clear coat. Needs paint repair.

Scratch-removal pastes and pens are abrasive. Used by hand without the right technique, they often leave a hazy patch or a ring of fine scratches around the original mark, and on dark paint that can look worse than the scratch did. Pens mostly fill the scratch temporarily and wash out. If the car matters to you, have it looked at before you try them.

Professional paint correction uses a machine polisher with matched pads and compounds, working panel by panel under strong lighting. Light swirls may need a single stage; deeper clear coat scratches may need two or more. A careful studio measures how much clear coat there is before removing any, because clear coat can only be polished a limited number of times.

• Wash safely: two buckets, a clean wash mitt and microfibre towels. Avoid automatic brush washes and dry wiping dusty paint.
• Ceramic coating: makes the surface slicker so dirt washes off more easily and fewer wash scratches build up. More on ceramic coating.
• PPF: self-healing film takes light scratches, which fade with heat, instead of the paint. More on PPF.