Frosting
Frosting is the name for car theft that happens when a driver leaves the car unattended with the engine running to defrost it.
Last updated: 19 October 2026
What it means
The AA says thieves target unattended cars with the engine running on frosty mornings, a crime it calls frosting. It advises staying with the car while the engine runs, and if you go indoors, switching off and locking the car. It also says insurers may not cover theft where keys were left in an unattended car [1].
Why it matters when you buy
If you buy a de-icer or scraper, plan to use them while you stay with the car. Regulation 107 says you must not leave a motor vehicle on a road that is not attended by a person licensed to drive it unless the engine is stopped and any required parking brake is set. The exceptions listed are for emergency service and certain work uses, not for defrosting [2].
Related
- How to clear an iced windscreen safely
- De-icer: how to clear a frozen windscreen
- Ice scrapers: how to choose and use one
Sources
- How to defrost a car windscreen: step-by-step guide, The AA, theaa.com. The page shows no date. Checked 19 October 2026.
- The Road Vehicles (Construction and Use) Regulations 1986, regulation 107, legislation.gov.uk. Checked 19 October 2026.