Registrations of new cars fell by 2.0% last month, new figures show.
Some 82,908 new cars were registered in August, the Society of Motor Manufacturers and Traders (SMMT) said.
The figure compares with 84,575 during the same month in 2024.
Battery electric vehicles held a 26.5% share of the new car market in August, which was the highest monthly level this year.
August is one of the quietest months of the year for new car sales as many people delay purchases until new number plates are introduced in September.
SMMT chief executive Mike Hawes said: “August was the best month yet this year for EV market share and while it is often volatile due to low overall volumes, the overall trend is positive.
“September will be critical, with the new number plate factor typically driving around one in seven new car registrations for the year.
“There is now a vast choice of electric models across all segments and many consumers will also, for the first time in three years, benefit from a grant to help them switch to electric.
“With more models being added to the Government’s electric car grant each week, there is now every reason for drivers to make the switch, helping deliver both economic growth and decarbonisation.”
The grant gives a discount of £1,500 or £3,750 off the purchase price of specific EVs, based on their sustainability criteria.
Cars must be priced at no more than £37,000 to be eligible.
Transport Secretary Heidi Alexander said: “Our electric car grant is driving down costs, making it cheaper than ever to go electric whilst putting money back in people’s pockets as part of the plan for change.
“This summer we’ve announced 35 models as eligible for the discounts and results speak for themselves – EV sales share in August is up 24% on July.”
Ian Plummer, chief commercial officer at online vehicle marketplace Auto Trader, said: “The Government’s £650 million electric car grant helped reignite consumer interest for EVs, with advert views for new EVs under £37,000 virtually doubling overnight.
“Consumers are keeping a close watch and as more eligible models receive the grant, we’re seeing them attract more attention on our platform.”
Tanya Sinclair, chief executive of lobby group Electric Vehicles UK, said: “Drivers are choosing electric vehicles, and are encouraged by a package of Government policy and incentives to support their switch to EV.
“With more than one in three new cars now having a plug, and one in four pure electric, it’s clear that drivers will make the switch when given what they need – outstanding vehicles with best-in-class tech, charging options at every speed, and a marketplace of competitive energy and financing offers.”
