229Mileage allowance payments
(1)No liability to income tax arises in respect of approved mileage allowance payments for a vehicle to which this Chapter applies (see section 235).
(2)Mileage allowance payments are amounts, other than passenger payments (see section 233), paid to an employee for expenses related to the employee’s use of such a vehicle for business travel (see section 236(1)).
(3)Mileage allowance payments are approved if, or to the extent that, for a tax year, the total amount of all such payments made to the employee for the kind of vehicle in question does not exceed the approved amount for such payments applicable to that kind of vehicle (see section 230).
(4)Subsection (1) does not apply if—
(a)the employee is a passenger in the vehicle, or
(b)the vehicle is a company vehicle (see section 236(2)).