Where your employees use a company car or van, but pay for the fuel themselves, the company can pay a fuel-only mileage rate for business journeys. This fuel-only rate is guaranteed to be tax free when it is equal to or less than the advisory fuel rates set by HMRC. These advisory fuel rates are now revised every quarter. The latest rates applicable from 1 September 2011 are shown below for different engine sizes, with the previous rates that applied from 1 June to 31 August 2011 shown in brackets. 

Petrol & LPG Engines
1400cc or less: Petrol 15p (15p), LPG 11p (11p)
1401 to 2000cc: Petrol 18p (18p), LPG 12p (13p)
Over 2000cc: Petrol 26p (26p), LPG 18p (18p)

Diesel Engines
1600cc or less: 12p (12p)
1601 to 2000cc: 15p (15p)
Over 2000cc: 18p (18p)

Note there is now a different scale for diesel vehicles.

The advisory fuel rates are based on average fuel prices per litre:

- Petrol: 134.6p 
- Diesel: 139p 
- LPG: 75.8p

If the prices in your local area are significantly higher, or your company cars are less fuel-efficient than average, you can pay a higher mileage rate. You need to keep a record of how you calculated that higher rate.

Where your employees use their own cars for business journeys, you can pay a tax free mileage rate of 45p per mile for the first 10,000 business miles driven in one tax year, and 25p per mile for extra miles in the same year. This rate was increased from 40p per mile on 6 April 2011, so remember to pay the higher rate to your employees and to yourself when you undertake business journeys in your own car.

Where the company is VAT registered it can reclaim VAT on the fuel element of mileage rates paid to employees, if the employee supplies the company with VAT receipts for fuel showing enough VAT to cover the claim. The advisory fuel rates are purely for fuel. The 45p per mile rate is only partly for fuel, the excess above the advisory fuel rate is to pay for other costs of running the car which are incurred by the employee.

If you are self-employed, with an annual turnover below the VAT threshold of £73,000, you can use the 45p rate as an approximation for the cost of business journeys in your own car.