Insurance costs are based on a combination of data and statistics that have been converted into a banding system. Every new car sold in the UK falls into a list of 50 insurance groups, and the higher the band number, the higher the insurance premium.
Insurers meet every month to review the vehicles in each band. The categorisation of each car reflects a mix of specification data (engine size, performance, initial purchase cost etc) and 'real-world' data that considers the statistical probability of claims being made by owners, and the cost of repairs resulting from those claims.
Repair costs account for more than half the money paid out through insurance claims. Premium manufacturers charge premium prices for both parts and labour, so their products fall into higher insurance bands than cheaper, low-specification models with smaller engines.
At the cheapest end of the insurance system you'll find cars such as the Volkswagen Up in band 2. So are most versions of Toyota's Aygo city car. Interestingly, the Peugeot and Citroen versions of the Aygo, the 107 and C1, are rated slightly higher than the Toyota (bands 3 to 4) even though they're virtually identical. That could be as a result of shorter repair times, more competitively priced common-repair parts, or the perception of a dealer network's efficiency.
Moving up the scale, we can see how engine specification and performance can affect premiums by looking at the Ford Focus range. Focus insurance ratings start in band 7 for the 85bhp 1.6 Studio, but rise to band 25 for the 1.6T Ecoboost Zetec S – it's the same engine size, but turbocharged to produce 180bhp. Similarly, the Volkswagen Golf starts in band 11 for the 85bhp 1.2 TSI, but peaks at band 30 for the 170bhp 2.0 TDI.
Further up the system, we find the Audi A7 Sportback 3.0 TDI quattro and BMW 530d SE in band 40.
In the very top grouping, band 50, you'll not be shocked to discover supercars from marques such as Aston , Ferrari and Lamborghini – but you might be surprised to find more prosaic machinery there too; the BMW X5 4.4 and Lotus Evora 3.5, for example.
You can find out which insurance band the car you're considering is in by looking in the data section of our car reviews but here's a selection of cars that are cheap to insure.
Top 10 cheap to insure - Group 1 - 5
The following cars have have versions that sit in insurance group 1 to 5.
Our reviews are based on hard data and thorough testing in the real world.
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