Published 27/09/2026 · Updated 27/09/2026 · By Voldt® product team

HMRC lets an employer repay the electricity used to charge a company car at home without a benefit-in-kind charge, as long as it can show the electricity went into that car. A record of each charging session is the simplest proof (HMRC Employment Income Manual, EIM23900). A portable 3-pin charger that logs every session in its app gives the driver that record from an ordinary socket.

Voldt® app · session log

Plugged in

21:40

Unplugged

06:10

Current

10 A

User

Driver 1

Total
energy

19,6kWh

Duration

8 h 30 min

✓ Saved in the Voldt® app

LOGGED

Benefit-in-kind rates for fully electric company cars are set at 4% for 2026/27, 5% for 2027/28, 7% for 2028/29 and 9% for 2029/30 (HM Treasury). Plug-in hybrids with 1 to 50 g/km of CO2 are banded by electric range until April 2028, then move to a flat 18%, rising to 19% in 2029/30.

For a car on a four-year lease signed now, that step lands in the second year, so a hybrid ordered today costs its driver more in tax before the lease ends. Each fully electric car that charges at home adds a bill on the employee's own supply, and the employer needs the car's share of it, separated from the household's.

HMRC changed its guidance in 2023: repaying part of a domestic energy bill used to charge a company car or van falls within the exemption in section 239 of the Income Tax (Earnings and Pensions) Act 2003. No benefit in kind arises, whether the miles are private or business (EIM23900). The condition is proof that the electricity went into the company car.

The alternative is the advisory electricity rate: from 1 September 2026, 7p per business mile for home charging and 15p for public charging (HMRC advisory fuel rates). It needs no meter reading, but it covers business miles only, and commuting counts as private travel.

With a record per session, the employer can repay every kWh the company car took at home at the driver's unit rate. At the Ofgem price cap of 26,32p per kWh for October to December 2026, a 20 kWh charge costs £5,26.

A smart meter shows when electricity was used, but not which part went into the car. Any split of the household total is an estimate, and an estimate is hard to defend as proof that the electricity went into the company car. The meter also cannot tell a company car from a second, private car on the same drive.

The car's app measures after the losses in the car. In a German test by the motoring club ADAC, five current EVs lost 12,7 to 24,2% of the electricity drawn from a 2,3 kW household socket before it reached the battery; at an 11 kW wallbox the loss was 5,1 to 7,0% (ADAC, August 2026). Repaying from the car's app underpays the driver by that share.

The charger's control box measures before the car, so the losses in the car are part of the logged kWh, as they are on the electricity bill. A 3-pin socket at 10 A draws the same 2,3 kW as in the ADAC test, so charging from it matches the household-socket panel in Fig. 3.

The Voldt® app connects to the charger over Wi-Fi or Bluetooth and keeps a session history with the energy of every charge. Several users can be linked to one charger, each with an individual usage log, so a pool car or a shared drive keeps the sessions apart. The records export for expense claims.

This route suits fleets that handle expense claims monthly, and it needs no back-office contract. A fleet that wants sessions to flow into a fleet platform on their own needs a charge point that speaks OCPP, the open protocol between charge points and back-office software.

The charger adjusts between 8 A and 13 A on its own, depending on the load on the circuit, or you set the current in the app or on the control box. At 13 A it draws up to 2,8 kW; at 10 A about 2,3 kW. For a car that does 3,5 miles per kWh, 20 kWh covers around 70 miles.

Most UK homes are single-phase, so a fixed wallbox tops out at 7,4 kW, about two and a half times the 3-pin maximum. For a driver who covers long distances every day, that difference decides the choice; a commute of up to about 60 miles a day fits in one overnight session.

A wallbox needs an installation, a place on the wall and, in rented homes, the landlord's consent. When the employee leaves, someone has to remove it or buy it out. The portable charger needs none of that and moves with the car, which suits renters, drivers who may change job within the lease and pool cars.

For a driver with a drive and high mileage, a fixed wallbox remains the better option. A mixed fleet can use both: wallboxes for long-term drivers who own their home, portable chargers for renters, pool cars and anyone likely to move. If every session should reach a fleet platform without exports, choose OCPP wallboxes for those drivers.

• Plug the charger straight into a sound, earthed 3-pin socket, never an extension lead or adaptor.
• Use the 13 A setting only on a socket on its own circuit that an electrician has checked.
• Where your car's manual differs from this guide, follow the manual.

Voldt® cables and portable chargers are CE and UKCA marked and TÜV certified, with a 3-year warranty; terms and exclusions are on the warranty and complaints page.