What costs the most to run a car?

For most drivers depreciation is the single largest cost, followed by fuel, then insurance.

How can I accurately track my real-world car running costs throughout the year?

The most reliable approach is keeping a simple log of every cost — fuel, insurance, MOT, servicing, tyres, repairs, and parking — in a spreadsheet or budgeting app. Recording your odometer reading monthly lets you calculate a rolling cost-per-mile figure, the most useful metric for comparing vehicles. tax authority's approved mileage rate of 45p per mile for the first 10,000 miles serves as a useful benchmark for a typical car including depreciation, fuel, and wear.

Car Running Cost Calculator UK

Useful next calculations

Use the Fuel Cost CalculatorContinue with the related car & transport question this result raises.
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Rates and sources

DVLA, HMRC fuel advisory rates and manufacturer-published figures. Real-world results vary by driving style.

Source: DVLA / HMRC fuel advisory rates. Check the linked guidance and any live quote before acting.

When to use this calculator

When you need a fast estimate before making a bigger decision.
When you want to compare a few scenarios using the same assumptions.
When you need a clearer starting point before using a detailed quote or formal document.
When you want to sanity-check a figure you have seen elsewhere.

A worked example

These are the example figures the calculator opens with.

A worked example
Input	Value
Car Value (£)	£15,000
Annual Miles	10,000
MPG	40
Fuel Price (£/litre)	£1.52

For those figures the calculator returns:

Annual cost: £5,357.51
Monthly: £446.46
Per mile: 53.58p

Method & assumptions

This calculator aggregates the major components of annual car ownership cost in the UK: fuel, insurance, road tax (VED), servicing, MOT, tyres, and any financing payments. Enter your best estimate for each category based on your actual bills or quotes. The calculator then produces a total annual cost and, divided by your annual mileage, a cost per mile figure. This pence-per-mile metric is particularly useful for comparing ownership of different vehicles or for calculating mileage reimbursement. Note that depreciation — often the single largest cost of car ownership — is not included here; use the dedicated depreciation calculator alongside this tool for a complete financial picture.

Common mistakes

Using optimistic assumptions without testing a more cautious scenario.
Comparing outputs from different tools without checking that the inputs match.
Treating the result as a final quote instead of a planning estimate.
Rounding inputs too aggressively.

What to do next

Try at least one more scenario so you can compare a realistic range.
Use the related calculators below to cross-check the decision from another angle.
Write down the key outputs from your best scenarios before you decide.
If the result surprises you, change one input at a time to isolate the driver.

Questions people ask

tax authority's approved mileage rate is 45p per mile for the first 10,000 miles, which broadly reflects average costs including depreciation, fuel, and wear for a typical car.