Written by the Autosparx team, TASSA registered auto electrical and vehicle security specialists based at the Historic Dockyard in Chatham, Kent. Fitting alarms, immobilisers, ghost immobilisers and trackers across Kent and the South East since 1991.
The short answer
To stop keyless car theft you need to break the one thing thieves rely on, which is your key fob’s signal. The quickest wins are free or cheap: store your keys well away from doors and windows, keep them in a Faraday signal blocking pouch that costs under £10, and turn off the fob’s wireless signal overnight if your car allows it. For proper, lasting protection, layer a visible deterrent like a steering wheel lock with a covert ghost immobiliser, which stops the engine starting without a secret PIN and cannot be beaten by a relay attack. Add a Thatcham approved tracker and you have the recovery insurance to match. In Kent, our mobile fitters can install a ghost immobiliser or tracker at your home or workplace, usually in one to two hours.
What is keyless car theft and how does a relay attack work?
Keyless car theft, often called relay theft, is when criminals steal a car with keyless entry and push button start without ever touching your key. It is now the dominant method of vehicle theft in the UK, with industry estimates putting relay and keyless exploitation behind between 60 and 70 percent of modern car thefts.
The most common version is the relay attack, and it takes two people and two handheld devices. One thief stands near your house holding a device that picks up the faint signal your key fob is constantly broadcasting, even from a bowl by the front door. That signal is relayed to a second device held next to your car. The car is fooled into thinking the genuine key is present, unlocks, and lets the engine start. The whole thing can take under a minute and makes almost no noise.
There are two other methods worth knowing. Signal jamming blocks your fob so the car never locks in the first place, leaving it open for the taking. OBD key cloning is where a thief plugs a device into your car’s diagnostic port and programs a blank key in seconds. A good security setup needs to shut down all three routes, not just one.
How big is the problem in 2026?
Big, and it is not going away on its own. DVLA figures show 54,145 vehicles were reported stolen across the UK in 2025, which works out at roughly 148 cars every single day, or about one every ten minutes. More than a quarter of cars on UK roads now have keyless entry, and those are exactly the models thieves target.
It is not only prestige cars either. The Toyota C-HR topped the 2025 most stolen list, with the Ford Fiesta close behind, proving that everyday family cars are firmly on the radar. In London and the South East, high value SUVs such as the Range Rover remain a favourite, with around 65 percent of premium thefts in the capital involving a relay attack. If you drive a common target and park on a Kent driveway or street, this is a real risk rather than a rare one.
Did the law change stop keyless theft?
Partly, and it helps, but it does not protect your specific car. The Crime and Policing Act received Royal Assent on 29 April 2026 and made it a criminal offence to possess, import, manufacture or sell the electronic devices used to steal vehicles, including relay tools, signal jammers and key emulators. Offenders now face up to five years in prison, an unlimited fine, or both.
This matters because until now only using these devices was illegal, not simply owning one, which made prosecutions hard. Closing that gap gives police a much stronger hand. That said, a law on the statute book does not physically stop a determined thief outside your house tonight. It is a deterrent, not a lock. The practical protection still comes from what you fit to your car and how you store your keys, which is where the rest of this guide comes in.
How to stop keyless car theft: the methods that actually work
There is no single silver bullet, so the smart approach is layered defence. Combine something that hides your key signal, something a thief can see and wants to avoid, and something hidden that stops the car dead. Here is how the main options compare.
| Method | Roughly what it costs | How much it helps | Best for |
|---|---|---|---|
| Faraday signal pouch | Under £10 | Blocks the fob signal thieves relay | Every keyless car owner, tonight |
| Storing keys away from doors | Free | Makes the signal harder to grab | Everyone, no excuses |
| Steering wheel lock | £30 to £100 | Strong visible deterrent, slows theft | Anyone wanting a cheap physical barrier |
| OBD port lock or cover | £20 to £60 | Blocks diagnostic port key cloning | Cars targeted by OBD attacks |
| Ghost immobiliser | £449 to £599 fitted | Stops the engine starting, beats relay and cloning | Modern, keyless and high value cars |
| Thatcham approved tracker | £150 to £500 fitted plus subscription | Locates and recovers the car if stolen | Insurer requirements and prestige cars |
Free and cheap steps you can take tonight
Start with the basics because they cost almost nothing. Keep your keys well away from the front door, ideally upstairs and inside a metal tin or a Faraday pouch, so the relay device cannot pick up the signal. A signal blocking pouch costs less than a takeaway coffee and is the single best value security buy you can make. If your key has a button to disable its wireless signal overnight, use it, and check the handbook because many newer fobs offer this. Never leave a spare key in the car or a coat pocket by the door.
Visible deterrents that make thieves move on
Thieves want a quick, quiet job. Anything that turns your car into a slow, noisy target sends them looking for an easier one. A bright steering wheel lock is impossible to miss and takes real time and force to remove. A lockable driveway post, a gear or pedal lock, and even a well positioned security camera all add friction. These will not stop the most determined gang on their own, but as one layer they genuinely work.
The covert layer that stops the car dead
This is where you move from slowing a thief down to stopping them completely. A ghost immobiliser is a small device wired discreetly into your car’s electronics that requires a unique PIN sequence, entered using buttons you already have such as the steering wheel or door controls, before the engine will start. There is no extra fob for a thief to relay or clone, and it defeats both relay attacks and OBD key cloning. It is silent, invisible, and has no subscription. For most keyless cars in 2026 it is the most effective single upgrade you can make, and we explain the technology in full in our guide to how a ghost immobiliser works.
The recovery layer for when prevention is not enough
Even the best prevention can be beaten by a truck and a determined crew who simply tow the car away. A Thatcham approved tracker is your safety net. It links your vehicle to a 24 hour monitoring centre that spots unauthorised movement, verifies the theft and works with police to recover the car. Insurers often require one on higher value models, and it can trim your premium too. If you are weighing which category you need, our guide to the Thatcham S5 vs S7 tracker difference breaks it down.
Ghost immobiliser or tracker: which should you fit first?
This is the question we hear most, and the honest answer is that they do different jobs. A ghost immobiliser is prevention, because it stops the car being driven off in the first place. A tracker is recovery, because it helps get the car back after it is taken. For pure keyless theft prevention, the immobiliser is the priority because it removes the reward for the thief entirely. For meeting an insurer’s condition or protecting a high value car against being towed, add the tracker as well. Many of our Kent customers fit both at the same visit, which works out cheaper than two separate appointments. We compare the two directly in our ghost immobiliser vs tracker guide.
Do I really need professional security if my car has factory immobilisation?
Almost every car built since 1998 has a factory immobiliser, and that is exactly the system thieves have learned to walk straight past. Factory security relies on a chip in the key, which relay and cloning attacks are designed to defeat. A modern aftermarket immobiliser adds a layer the thief cannot see and has no way to bypass with a relay box. In short, factory security is the baseline, not the answer, in 2026. If you want the full picture on adding protection, see our guide to professional car immobiliser fitting in Kent.
Protect your car in Kent with Autosparx
We have been fitting vehicle security across Kent and the South East since 1991, and keyless theft is the problem we solve most often. Our TASSA registered fitters can install a ghost immobiliser, a Thatcham approved tracker, or a full layered setup at our Chatham workshop or at your home or workplace anywhere in Kent, usually in one to two hours. To protect your car properly, book a ghost immobiliser installation or explore our vehicle security systems and give us a call for an exact quote on your make and model.
Frequently asked questions
Can any keyless car be stolen in a relay attack?
If it has keyless entry and push button start and no extra security, then yes, it is vulnerable. The fob broadcasts a signal that a relay device can capture and extend. Blocking that signal with a Faraday pouch and fitting a ghost immobiliser removes the vulnerability.
Does a Faraday pouch really work?
Yes, when it is a good one and you use it properly. A quality signal blocking pouch stops the fob’s signal escaping, so a relay device outside your home has nothing to grab. Test it by locking the pouch, standing next to your car and checking that it will not unlock. Replace the pouch if the lining wears out.
Will a ghost immobiliser stop a relay attack?
Yes. A ghost immobiliser does not rely on the key signal at all. Even if a thief relays your fob and gets into the car, the engine will not start until the correct PIN sequence is entered on buttons inside the car. There is no fob to clone and no signal to relay.
Does keyless theft protection lower my insurance?
It can. Insurers often recognise Thatcham approved trackers and TASSA verified immobilisers, and fitting one may reduce your premium or satisfy a condition of cover on a high value car. Always tell your insurer what you have fitted.
Is it illegal to own a relay device now?
Yes. Under the Crime and Policing Act 2025, possessing, importing, making or selling electronic devices used for vehicle theft is a criminal offence carrying up to five years in prison. Previously only using them was illegal.
