The taxable company car fuel benefit charge is calculated by multiplying the fuel benefit charge multiplier by the same percentage as applies for the car benefit, which is based on the CO2 emissions of the car.
It is the view of the UK government that the provision of free fuel to company car drivers provides a perverse environmental incentive. Consequently from 6 April 2010 the fuel benefit charge multiplier was increased from £16,900 to £18,000 per annum which will increase the total cost of the benefit for both employee and employer. If the employee pays for the full cost of all fuel for private journeys (such as home to work) there will be no car fuel benefit. In all other cases, the full tax charge will be due. Note that the increase covers a two year period, and is in reality less than fuel price inflation over the same period.
Our fuel cost calculator might be a further source of information.
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