The era of two fuels is over: diesel popularity is waning as renewed low-CO2 tax incentives push company car drivers to swap pumps for chargers. But the tax system hasn’t kept up.
HMRC still doesn’t treat electricity as a fuel, which can cause unnecessary costs for electrified fleets. Here’s how to avoid them.
BEV mileage rates – fit for purpose?
HMRC publishes Advisory Fuel Rates (AFRs) for every quarter, grouped by engine size and fuel type and adjusted in line with pump prices and average vehicle efficiency. The Advisory Electric Rate (AER) introduced in 2018 provides something similar for BEV drivers charging at home – where it’s harder to separate costs from the rest of a utility bill – but is nowhere near as granular.
BEV efficiency is just as variable as that of petrol and diesel cars, so a big SUV will cost more per mile than a city car, but the AER doesn’t recognise this. Despite the recent increase from 4p per mile to 5p per mile, due to rising energy costs, it can leave drivers out of pocket even if they’re charging at home.
Autocar's company car tax calculator shows exactly what you'll pay for every make and model
| Flat rate cost per mile | Dual rate peak | Dual rate off-peak | |
|---|---|---|---|
| Audi e-tron 50 quattro S-Line | 7p | 8p | 4p |
| MG5 Excite Long Range | 5p | 6p | 3p |
| Polestar 2 Long Range Single Motor | 5p | 6p | 3p |
| Kia Niro EV 3 | 5p | 6p | 3p |
| Volkswagen ID.3 Life Pro Performance | 5p | 5p | 3p |
| Fiat 500 Icon Hatchback | 4p | 5p | 3p |
Source: Dept. BEIS UK average unit costs, 2021 (18.9p flat, 22.0p peak, 11.0p off peak)
Fleets have also expressed concerns that the rate isn’t keeping pace with energy prices which, according to Government data, were 45% higher in the second quarter 2022 than they had been a year previously. The Energy Price Guarantee introduced in October 2022 has capped electricity at 34p/kWh until April 2023, which equates to charging costs of 8p/mile for the Fiat 500 shown above.
HMRC does offer some flexibility to cover this, though. Fleets can repay drivers on a per-unit (kilowatt-hour) rate to cover home charging or adjust the rates to match their costs, but it’s up to them to prove that the rates are realistic. If an audit suggests the employer is making a profit or effectively providing extra income to employees, then both are taxable.
Public charging presents slightly different headaches. Most networks will let drivers request a VAT receipt for expenses, and some fuel cards now include chargepoint access within a single account, too.
the fastest and most convenient chargers usually cost twice as much as plugging in at home. For example, Ionity’s ultra-fast units cost almost four times more per unit than the UK domestic average – so it could be worth encouraging drivers to make a slight detour to keep a lid on costs.
How do you incentivise PHEV drivers to plug in?
AFRs can also be problematic for PHEVs, which don’t have their own set of rates. Instead, drivers claim using the petrol or diesel rates, based on their engine capacity, and these are unlikely to reflect hybrid economy – let alone plug-in hybrid economy.
From 1 September 2022, the rates are as follows:
