Best car security: the most secure cars

Keep crooks away with a secure car that's properly protected: read on for the best car security

John Evans
Oct 8, 2021

Regardless of how much you may have spent on your car, the last thing you want is to have it stolen. Sadly, although security technology continues to improve, car theft is still a major concern for many UK drivers, with over 89,000 car thefts reported last year alone.

There are a number of things you can do to help protect your car, as we explain below. They include choosing a car with a good level of standard security (for example, one equipped with a Thatcham Category 1 alarm and immobiliser), putting some extra thought into your parking (in brightly lit areas, facing your house and with no valuables on view) and investing in some extra security-based products. If your car is especially valuable, it is worth considering a tracking device so it can be traced and returned.

If you are looking at buying a new car, it’s a good idea to check its security rating beforehand. Every year, Thatcham Research, the vehicle research centre owned by the insurance industry, tests the security systems of 130 new and facelifted models as part of its New Vehicle Security Assessment (NVSA) programme. It awards each car a star rating for its security against theft of the vehicle and theft from it - in a similar way to the Euro NCAP safety rating system.

The maximum score a car can achieve in each category is five stars. ‘Theft of’ the vehicle is the category Thatcham attaches most weight to. The results of its tests feed into its group ratings that insurers then use to determine a vehicle’s risk profile and your premium.

As a general rule of thumb, larger models achieve five stars more easily than smaller ones. One of the few city cars to achieve five stars is the Smart ForTwo, and one of the few superminis, the Audi A1.

Partly as a result of the recent rise in car crime, Thatcham is taking a fresh look at how it tests and assesses cars’ security systems, especially the security of their on-board diagnostic (OBD) ports and keyless entry systems.

Legislation requires that the OBD port that provides direct access to the car’s control systems must be accessible by anyone, by which it means independent garages as well as more expensive franchised ones. The problem is, thieves can also access them and, by using devices freely available on the internet, manipulate the software and steal the vehicle.

We’ve all seen CCTV footage of thieves stealing expensive cars with keyless entry and ignition systems from driveways. This is called keyless entry theft and involves the thief using a device, again very likely sourced from the internet, that fools the car’s systems into believing they have the real key.

Thatcham’s latest tests and assessments test the systems put in place by car manufacturers to protect OBD ports and keyless systems without making them inaccessible to legitimate users.

What are Thatcham’s vehicle security categories?

Thatcham Research, the motor insurance industry’s research centre, tests and rates security systems and aftermarket security products, awarding them a category status from 1 to 7 that reflects their performance and specification.

Category 1 This is the smartest car security system and features an alarm with multiple sensors, a siren with its own power supply and an immobilizer that sets itself. This level of security is often found in more expensive cars.

Category 2 This system features an electronic immobiliser only. Again, it has to be capable of setting itself without any action from the driver. Most cars have this level of security as standard.

Category 2/1 This is awarded where a category 2 immobiliser is supplemented by a category 1 alarm. This would typically be an aftermarket installation on a car.

Category 3 This applies to permanent or temporary mechanical devices such as steering wheels and pedal locks. Thatcham tests these separately and makes recommendations. Look for its logo on the packaging.

Category 4 Locking wheel nuts requiring a dedicated key to release fall into this category. There must be a secure replacement key service and they must be traceable, and withstand sustained attack. Most new cars with alloy wheels have locking wheel nuts as standard.

Category 5 This applies to tracking systems that can locate a stolen car and disable it remotely. Tracker systems do not come as standard on cars but are fitted separately.

Category 6 As category 5 except they cannot remotely shut down a vehicle.

Category 7 Very like category 6 with remote immobilisation not permitted.

Q class Aftermarket systems and devices including vehicle marking and ID, and alarms and immobilisers that have not been approved by Thatcham.

How can I secure my car?

It’s tempting to think that keeping your car safe from thieves is a matter of closing the windows and locking the doors, and relying on whatever additional security systems the vehicle has to do the rest. However, if it were that simple, car theft wouldn’t be such an issue.

To avoid being a thief’s next victim, experts recommend you take a 360-degree approach to vehicle security, taking into account not only the car’s security features but any more that you can add - such as how and where you park, and whether you have left anything on view inside the car that could attract a passing thief.

Fortunately, there are a few common-sense things a vehicle owner can do to make things as difficult as possible for a thief, helping buy time for the alarm to be raised.

Keep the vehicle locked Modern cars’ smoother locking mechanisms can make it difficult to hear if the car locks. Double-check that it is locked before leaving your vehicle, even if you are just ducking away for a few minutes. Never leave the vehicle running when you are not with it, and unless you have a secure parking garage, ensure the car is locked when parked outside your home.

Invest in the right technology Most modern cars are fitted with alarms and immobilisers as standard. However, thieves’ knowledge of the latest security systems is keeping pace with manufacturers’, so investing that bit more into your car’s security could make a real difference. Steering wheel, pedal and gear locks are inexpensive, easy to install and off-putting to criminals, while tracking devices or CCTV systems fitted near your car can help track down your vehicle and the perpetrator should it be taken.

Keep your keys safe The easiest way for a criminal to steal a car is by taking the keys, so always ensure you store your keys out of sight of doors or windows.

Block signals Some manufacturers make it possible to switch your key off. If this is not possible for your car, put your key in a signal-blocking container or pouch.

Park smart If you don’t have the luxury of a private garage or off-street parking, try to park in a well-lit, populated area whenever possible. Thieves will primarily target vehicles left in areas where they have little chance of being seen, so parking in side roads or areas away from street lights could put your vehicle at increased risk. If you've only limited parking space, check out some of the easiest cars to park.

How to prevent car theft at home

You’d think that being parked on your driveway, your car would be safe from theft but as CCTV images of cars being stolen from immediately outside their owners’ homes shows, this is not the case.

Fortunately, there are some simple precautions you can take to prevent your car from being stolen from outside your home, or at least discourage a thief from considering doing so…

Park so the car is facing your house This discourages the casual thief who realises he has to reverse the vehicle to make his escape.

Block your car in It might delay your departure in the morning but parking a less desirable car behind yours will make the thief’s job doubly hard.

Don't leave your car with the engine running Even if you’re popping back into the house for a quick moment, switch your car off and lock it. A passing car thief can drive off with your car in the blink of an eye, and with the keys in the ignition and the engine already on, it is practically an invitation to do so.

Keep your car’s interior tidy A messy interior with valuable objects such as a sat nav on view shows a thief you’re disorganised with little concern for security. Tidy it up and keep valuable items out of sight, or better still remove them altogether.

Keep handbags and keys out of sight and reach in your home Anything that might contain your car key is an open invitation to a thief bold enough to ‘fish’ for it through your letterbox or even smash a house window to get to it.

Turn the wheels towards the kerb or another car When parking on the street, anything you can do to slow the thief’s getaway, such as forcing him to manoeuvre the car out of its parking space, has to be worthwhile.

Install security lights No thief likes the glare of bright lights and they will also alert you to any movement on your property.

Install a CCTV camera If your car is particularly valuable, it’s a worthwhile investment that will discourage the less determined thief or at the very least help towards bringing the culprit to justice.

Best car anti-theft devices

A high number of cars are taken by thieves who have simply entered the vehicle through an unlocked door. This isn’t a case of owners forgetting to lock their cars, but instead, in an increasing number of cases it’s a method by which thieves can intercept your key’s locking signal to gain access to the car.

As a result, owners, especially of high-value vehicles that appear to be more at risk from this kind of crime, are investing in mechanical locking devices such as steering wheel and pedal locks.

Below are three security products tested and approved by Thatcham Research, the motor industry’s research centre:

Steering wheel locks

Stoplock Pro
This device clamps around the steering wheel spoke, making it more time-consuming to break and remove. It features case-hardened parts to help it withstand attack and, crucially, is easy to operate so more likely to be used.

Unlike Stoplock Pro, this device encloses the whole wheel, protecting it from attack. Attempt to overcome it and it just turns around the wheel. It’s heavy, though, and takes up room in your car when not in use so is not quite as user-friendly as the Stoplock Pro.

Pedal locks

Locking the car’s pedals is another effective way of making a thief’s life difficult. The PedalBox is a tough steel box that you place over the pedals, rendering them inoperable. However, although it’s bright yellow, it’s not as visible as a steering wheel lock and requires more space to store.

How to avoid keyless car theft

Many of us have seen those shocking CCTV images of crooks walking up to a locked car on a private driveway and, without a key, miraculously opening its doors before driving off.

Last year, half of the 89,000 vehicles stolen in England and Wales were taken by thieves who’d accessed them through an unlocked door. This compares with just 13% in 2006. Some thieves forced their way in but a larger, and growing, number simply unlocked the vehicle using devices available on the internet that enable keyless theft.

How is keyless theft committed?

Keyless cars require no key to physically unlock the car and turn on the ignition. Instead, the key’s mere presence close to the vehicle is sufficient to unlock the doors and allow the driver to press an ignition button to start the engine.

Keyless theft requires thieves to have a relay transmitter and a relay amplifier. Having identified the target car at the owner’s home, one of them stands by the car with the relay transmitter while the other moves around the outside of the house using the relay amplifier to locate the signal coming from the car key inside it.

When it locates it, the amplifier boosts the strength of the signal so that it can be received by the other thief’s transmitter. Once received, the transmitter instantly unlocks the car and its ignition system.

Here are security experts’ tips for avoiding keyless car theft:

Check if you can switch off your key Some keys can be switched off but it’s not obvious. Check your car’s handbook or consult your dealer.

Put your key in a security pouch So-called Faraday pouches block the key’s signal but not all of them have been tested and not all of them work. Those that do are certainly a good way of beating the keyless thieves but if you use it when you’re out and about, you lose some of the convenience of keyless entry.

Put the key in a metal tin This will help reduce the strength of the key’s signal

Keep the key away from windows The farther away from doors and windows you can put your key, the more likely its signal will not be intercepted.

Check if your car’s keyless system has been updated Your dealer will be able to tell you if there have been any updates to the keyless system that could improve your car’s security.

How to choose a vehicle tracker system

Few security systems can stop a determined car thief with time and privacy on their side but if they do manage to steal your pride and joy, it’s good to know there’s a system that can help you recover it.

Called a vehicle tracker, it’s a small transmitter fitted to your car where it can't be found by a thief and removed. It uses location technology to pinpoint your car and transmit this information to your phone, or a control centre, in the event that it’s stolen. Because it’s real-time information, the police can track your car as it is driven away, and intercept it.

Some trackers are more effective than others. For example, some can transmit from below ground or from a container, where others can't. Some are battery powered while others are hard-wired into the car.

Trackers aren’t cheap. Not only must you buy the device and pay to have it installed but you’ll also have to pay a monthly subscription.

What to look for

Discreet and durable
To be most effective, a tracker must be installed where it cannot be found by a determined thief. Most high-value cars have a tracker so it’s the work of an expert to install it in a discreet place. For this reason, it must have a tough, waterproof case and be able to transmit the car’s location in all conditions

GNSS module
If you choose a satellite-based tracker make sure it has a module combining four different satellite systems – GPS, GLONASS, GALILEO, GLONASS – into one to make sure you get the most accurate location anywhere in the world.

A VHF (very high frequency) tracker has the edge over GPS-based trackers since the signal cannot be jammed and can penetrate shipping containers and underground car parks.

Better still, have VHF and GPS
For belt and braces, choose a tracker combining VHF with satellite technology. Such systems are likely to have jamming countermeasures, and to issue suspected tamper and movement alerts.

On-demand real-time tracking
This feature lets you know at all times where your car is. Avoid those systems that store its location in the tracker’s memory for retrieval at a later time.

Location updates
For the greatest accuracy, choose a system that gives you location updates every 5 to 10 seconds. Any longer is of much less value.

Tracking app
Choose a tracker that has a mobile app so when you’re out and about you can monitor your car’s location.

Additional features
Features such as ignition alert that tells you if the engine has been started, free-of-charge notifications, and maps in satellite, road and hybrid forms are essential.

Global roaming
High-value cars are often stolen to order and shipped out of the UK very quickly. For this reason, choosing a system that can track your car abroad is essential.

Customer support
Having an expert at the tracker company that you can talk to at any time of the day or night is vital. Thieves keep irregular hours.


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