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HMRC internal manual

Employment Income Manual

HM Revenue & Customs
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Car benefit calculation Step 1, price of the car: exception: cars manufactured to run on road fuel gas

Section 146 ITEPA 2003

Before reading the guidance that follows this paragraph, ensure that you are familiar with:

  • the method statement in Section 121(1) ITEPA 2003, see EIM24015 (this page concerns step 1)
  • the general introduction at EIM24050 
  • the flowchart at EIM24055 
  • when list price is to be used, see EIM24100.

Cars affected

EIM24825 details the various kinds of gas and bi-fuel cars and summarises all the statutory adjustments to the car benefit calculation. It also contains links to the adjustments which apply to other types of bi-fuel car.

Only type C1 cars are affected by the adjustment on this page.

Reduction in price of the car

The price of these cars as found under step 1 of section 121(1) (see EIM24100) is reduced by so much of that price as it is reasonable to attribute to the car being manufactured in such a way as to be capable of running on road fuel gas rather than in such a way as to be capable of running only on petrol.

Normally, this will mean replacing the price of the car that can run on road fuel gas with the (lower) price of the petrol-only equivalent model.

Road fuel gas

This means any substance that is gaseous at a temperature of 15 centigrade and under pressure of 1013.25 millibars, and which is for use as a fuel in road vehicles. The two main types of road fuel gas that are currently in use are compressed natural gas (CNG) and liquid petroleum gas (LPG).