CA23535 | Plant and Machinery Allowances (PMA): cars: outline of rules
From HM Revenue & Customs · Capital Allowances Manual
CAA01/104A & 104AA
The capital allowances treatment of expenditure on a car depends on the carbon dioxide emissions of the car. In summary,
As described in CA23153, 100% FYAs can be claimed for cars which are unused and not second hand and which have zero CO2 emissions.
Main rate WDAs can be claimed for cars (including second hand cars) with low or middle range CO2 emissions.
Special rate WDAs can be claimed for cars with higher CO2 emissions.
The CO2 thresholds depend on the date of purchase. Details can be found on 'Claim capital allowances - Business Cars', gov.uk. For information about emissions figures, see CA23545.
If there is an element of non-business use of the car then the expenditure will still need to be allocated to a single asset pool in accordance with CA27005 but the rate at which WDA are given will depend on the car’s CO2 emissions.