The short answer
Putting a GPS tracker on someone else’s vehicle without their knowledge can be a criminal offence in the UK — covert tracking is a recognised form of stalking and harassment. Tracking your own vehicle is fine. For businesses, tracking an employee’s personal car is only defensible for work journeys, with the employee fully informed.
Not legal advice. This guide explains UK law in general terms, as at the date shown. The ICO’s guidance on monitoring workers was under review following the Data (Use and Access) Act 2025 when this was written — check the ICO for the current position, and take advice for your own circumstances.
Can you track a vehicle with GPS without the owner knowing?
You can track your own vehicle however you like. Tracking a vehicle someone else owns or uses, without their knowledge, is where the law comes in:
- Stalking and harassment. The Protection from Harassment Act 1997 lists behaviours associated with stalking, including “watching or spying on a person” and monitoring their electronic communications. The Crown Prosecution Service’s guidance treats covert surveillance as a stalking behaviour, and secretly tracking a partner’s or ex-partner’s car has led to prosecutions.
- Data protection. A business tracking a person without a lawful basis and without telling them is likely to breach UK GDPR.
If you are worried you are being tracked, see how to detect and remove a GPS tracker.
Legal issues with GPS tracking on personal vehicles used for work
Many small businesses rely on staff using their own cars or vans. You can’t fit a tracker to a car you don’t own without permission, and even with permission, tracking someone’s private journeys in their own vehicle is very hard to justify. The workable approach is to track the person during working time, not the vehicle all the time:
- Use a phone app the employee switches on at the start of a shift and off at the end.
- Put it in writing: what is tracked, when, why and who sees it.
- Keep only what you need, for as long as you need it.
Family and shared vehicles
Tracking a vehicle you own that a family member drives is a grey area that depends on circumstances. Being open about it is both the ethical and the legally safer approach; secret tracking of an adult family member or partner can cross into harassment.
Where TrackLink fits
TrackLink tracks a phone, not a vehicle, and only while its holder has switched tracking on — which makes it a natural fit for staff using their own vehicles for work, and unsuited to covert tracking by design.
Common questions
Is it illegal to put a tracker on someone's car in the UK?
Doing it covertly to monitor a person can amount to stalking or harassment, which are criminal offences. Tracking your own vehicle is lawful.
Can my employer track my personal car?
Only with your knowledge, and realistically only for work journeys. Continuous tracking of your private use would be very hard for an employer to justify.