Private car expenses are allowable as business expenses when travelling from your place of work to or from a client or supplier. Going from home to office is not considered a business expense.

There are two ways you can calculate these costs. The first is using a per mile amount given to us by HMRC called Approved Mileage Rates. Simply multiply the relevant mileage rate by the number of miles you have travelled for business.

The second is by calculating what % of your mileage is for business and then applying the % to the actual costs of running your car. For this you will need to know your business mileage, the total mileage of the car for the year and the total of all car costs in the year (road tax, petrol, insurance, repairs etc).