The cost of running a car

 The information in this guide was last updated on 26/02/2014

Although buying a car can be exciting and gives you independence, there are ongoing costs you will need to be aware of in maintaining it legally and road-worthy. Petrol costs are a big factor as the price has steady risen over the years. Other things to consider include insurance, road tax and servicing costs.

Running costs to consider...


Petrol or diesel?

One of the biggest decisions you'll need to take fairly early on is whether to choose a petrol or diesel car. Here are some of the deciding factors.

Fuel prices

Although the price of diesel at the pump tends to command a higher price than petrol, many diesel cars still boast superior fuel efficiency. That said, diesel cars tend to have a higher purchase price, so you need to decide whether there is actually a saving to be made in the long-run.

Residual values

You might have noticed that diesel cars seem to hold their value better than petrol models. But some surveys have found that diesel cars can be a little less reliable than petrol ones – and sometimes cost more to repair too. There's a lot to weigh up here, so be sure to do your homework.



Here are some of the best and worst-performing cars from CAP – the industry specialist.

Top 10 best for depreciation
Top 10 best for depreciation
Make/model future trade value*
Top 10 worst for depreciation
Make/model Future trade value
1 Porsche 911 Carrera Cabriolet 55.30% 1 Volvo S80 T6 19.30%
2 MINI Roadster Cooper SD 55.00% 2 Proton Gen-2 Persona 20.60%
3 Ferrari 458 Italia 53.60% 3 Vauxhall Insignia saloon 2.8T V6
3 Vauxhall Zafira 1.6i 21.70%
4 Morgan 4/4 1600 Tourer Sport 52.80%
5 Mercedes A-Class A180 CDI 52.30% 5 Citroen C5 saloon 1.6i 22.00%
6 Audi A3 1.6 TDI SE 52.20% 6 Cadillac CTS 3.6 V6 22.20%
7 Mercedes SLK 250 CDI 52.10% 7 SsangYong Rodius diesel 22.60%
8 Porsche Boxster 51.90% 8 Proton Savvy 1.2 Style 22.90%
9 Morgan Roadster V6 51.80% 9 Cadillac STS 4.6 V8 23.10%
10 BMW M135i 51.70% 10 Jaguar XJ Saloon 5.0 V8 23.30%

*The predicted worth, as a percentage, of the car bought new in 2012 then traded in with 30,000 miles on the clock in 2015. Source: CAP, August 2012



Being generally more fuel-efficient, diesel cars fall into a cheaper road tax band – which will save you a few quid every 6 or 12 months. You could even go for a car that's tax-exempt – typically electric-powered models or those with the best fuel efficiency.

Here are some to look out for:

  • Nissan Leaf
  • Fiat 500 TwinAir
  • Fiat Punto Evo
  • VW Golf 1.6TDi Bluemotion
  • Toyota Prius
  • Lexus CT200h

Some organisations provide special dispensation for disabled drivers, and you can find more from Motability.

Don't forget, cars made before 1 January 1973 do not need road tax.

To see how much your car will cost you, visit



Insurance costs will vary by model, so it's best to get a quick insurance quote before committing to anything.



Every car over three years old is legally obliged to have an annual MoT test. There's no getting around it, but you might be able to combine your annual service with the MoT and get a discount from the garage. There's no harm in asking.

At the very least, make sure you don't pay too much for the MoT test, by checking