According to figures obtained by motoring research charity the RAC Foundation, just 4,200 drivers applied for the plug-in car grant between April and June.
This is down from the 17,500 who submitted applications for the grant during the previous three months.
It follows the cut on March 1 in the amount of money available to motorists buying new electric or hybrid cars.
From this date, the grant was reduced from £5,000 to either £2,500 or £4,500, depending on zero-emission range.
In the view of the RAC Foundation, the drop-off has been caused by drivers seeking to buy their car before the subsidy was cut.
Steve Gooding, the charity’s director, said: “Given that a 5p charge for a plastic bag changed the shopping behaviour of millions, it should be no surprise that when thousands of pounds are at stake drivers are very shrewd about their buying decisions.
“The cost of green cars is pivotal to their take-up and the market will remain acutely sensitive to changes in price, whether that is driven by manufacturers or ministers.”
The current terms of the plug-in car grant state that those vehicles with a greater zero-emission range – more than 70 miles – are eligible for a subsidy of up to £4,500.
Buyers of vehicles with a shorter range, meanwhile, can receive £2,500. Typically, these will be plug-in hybrids with a petrol or diesel engine.
The Government has recently been criticised for failing to make sufficient effort to encourage drivers to make the switch to low-emission vehicles.
Parliament’s environmental audit committee said that ministers had not provided enough infrastructure or incentives to boost take-up of such vehicles.
It follows a warning last year from the Government advisory panel the Committee on Climate Change that 9% of new car sales should be electric vehicles by 2020 for the UK to meet its legal obligation to cut greenhouse gas emissions by 80% by 2050 compared with 1990 levels.
Nevertheless, demand for low-emission vehicles remains high. RAC Foundation figures show that the Mitsubishi Outlander plug-in hybrid is the UK's most popular ultra-low carbon car, with 66,000 licensed for use on UK roads.
The pure battery-electric Nissan Leaf is in second place at 13,000, followed by the BMW i3 - which is available as pure battery-electric or with a petrol engine to recharge the battery on long journeys - at 4,000.