Just over a third of company cars are diesel, down from 80% of the fleet in 2017, according to new data published by HMRC.
The proportion of company cars using diesel fell to 35% (245,000) in 2021/22, down from 49% (355,000) in the previous tax year (2020/21).
The number of petrol company cars increased year-on-year, from 315,000 to 345,000 in 2021/22, but it is electric vehicles (EVs) which have benefitted most from the switch away from diesel.
The figures from HMRC show that 17% of company cars – some 125,000 vehicles – were fully electric in 2021/22.
That is more than double the 50,000 electric company cars reported the previous tax year (2020/21), when electric vehicles accounted for 7% of the company car fleet.
The increase in electric company cars, which has been driven by low benefit-in-kind (BIK) tax rates, has helped reduce the average CO2 emission rate of company cars to 86g/km – down from 99g/km in 2020/21.
Even after excluding electric cars, the average CO2 emission rate has reduced to 103g/km, confirming a trend towards lower emission fossil fuel cars.
Two decades ago, in 2002/03, more than half (58%) of company cars had reported emissions in excess of 165g/km. That has now fallen to just 2% of the company car fleet due to fossil fuel cars becoming more efficient and an increasing share of company cars powered exclusively by electricity.