Car insurance groups are one of the many ways insurers work out insurance premiums. There are 50 insurance groups, 1 being the cheapest and 50 the most expensive. Every car in the UK is given an insurance group which is then used to work out insurance costs, along with other factors like postcode, age and occupation.

The motor insurance repair research centre (Thatcham) and the Association of British Insurers (ABI) decide which group a car goes in.

There are lots of things that Thatcham and the ABI look at when deciding which of the 50 insurance groups to place a car in. One of the biggest factors is the repair costs involved following an accident.

They also look at:

• Performance: the top speed and 0 – 60 mph acceleration, as high-performance cars are more likely to make insurance claims.
• It's new car price: the cost a new car shows how much it will be to replace if it’s a write-off.
• Parts pricing: a list of the 23 most commonly damaged panels and parts in an accident helps them work out the cost of repair. Due to the more sophisticated design and technology in modern cars, repairs and parts are more expensive than they ever were.
• Security: including the manufacturer’s standard fitted security features. Enhanced security features like alarms and immobilisers help protect your car against theft, and may also mean the car is placed in a lower insurance group.
• Average repair time: long repair times could mean a higher insurance group rating and higher costs as a result. 
• Car bumper: The performance of a bumper in an accident can also affect how the car is grouped.

To calculate repair costs, Thatcham engineers use an internationally recognised impact test where each car is put through a 15Km/h impact then assessed to determine the cost and time involved in returning the car to its pre-accident condition.

If Thatcham and the ABI have rated a car’s security features, you’ll see a letter after the insurance group number that shows the result of the security test:

E	Exceeds the security requirement for a car of this type and therefore the group rating has been reduced – e.g. a group 12 car that exceeds the standard is listed as a 11E
A	Acceptable security requirements for the car's group
P	Provisional – incomplete data when the model was launched
D	Doesn't meet the security requirement for a car of this type, therefore the group rating has been increased – e.g. a group 11 car that doesn't meet the standard is listed as a 12D
U	Unacceptable – the level of security is significantly below requirements. The car won't be uninsurable, but some insurers may insist on a security upgrade before they cover you
G	Import – Insurance Group Ratings and security ratings are currently only allocated to vehicles built for the UK market

You can check which group your car is in by visiting the Thatcham website. The cheapest car insurance groups are 1-10, so if you’re looking to keep car insurance costs low, choosing the right car can make your premium more affordable.

Some of the models you might find in the different insurance groups include: 

Group Range	Manufacturers & Models
1 - 10	Citroen C1, Vauxhall Corsa, Ford Ka, Audi A1, Volkswagen Polo
11 - 20	Audi A3, Fiat 500, Honda Civic, Kia Picanto, Mini Countryman
21 - 30	Audi Q5, BMW 1 Series, Land Rover Freelander, Mini Cooper S
31 - 40	Lexus IS, Audi TT, BMW 5 Series, Ford Mondeo, Porsche Boxster
41 - 50	Infiniti M, Volkswagen Phaeton, Audi R8, Citroen C6, Volvo XC90

*This is not an exhaustive list - some of the models within each group range will be allocated different groups depending on their exact specification. All details taken from Parkers.co.uk.

The proposed groupings are recommendations only, insurers can set their own groupings if they choose to.

Choosing a car in a low insurance group is a sure way to cut the cost of car insurance. But, there are others ways to help reduce costs:

• Increase your excess - increasing the amount of voluntary excess you're willing to pay towards a claim may help reduce your price.
• Fit extra security - enhancing the security in your car can help lower insurance costs. Safety measures such as where you park your car overnight can also help.
• Be accurate with your mileage estimation - over-exaggerating your annual mileage could end up costing you more. Try and be as accurate as you can, there's no need to pay extra for miles you're not driving.
• Add a named driver - having an experienced driver on your policy can help lower costs, but it’s important to list the person who drives the car the most as the main driver.
• No-claims bonus (NCB) - most insurers offer a discount if you haven’t made a claim, the more years NCB you have the bigger the discount.

Insurers work out insurance policy prices based on statistics and risk. If they feel you’re more likely to make a claim in the future (based on statistics) then this will be reflected in your price. That’s why young and new drivers usually pay more for their insurance than older, more experienced drivers.

The car you drive also affects the cost of your car insurance as well as:

• Where you live
• Your occupation
• Your driving history e.g. any points on your licence or disqualifications

Find out more about how insurers calculate car insurance.

Just like petrol or diesel cars, electric cars are also grouped from 1-50. Their group is determined in the same way. Because electric cars are still relatively new to UK roads and their parts are more specialised, they can be more expensive to repair after a crash. This means they can fall into the higher end of the grouping scale.

As electric cars become more popular and manufacturers start rolling out e-versions of their existing models, the price of repairs and parts should start to come down.

The following table shows you some of the lowest electric car groups in the UK: 

Group Range	Manufacturers & Models
10	Volkswagen E-up
14	Renault Zoe expression Nav
15	Volkswagen E-Golf
21	BMW i3
22	Nissan Leaf

Find out more about electric car insurance.