All cars, vans and motorcycles in Britain have been eligible to delay MOT testing since March 30 due to the pandemic, while drivers in Northern Ireland have been given a one-year exemption.
A separate report by road safety charity Brake and breakdown rescue firm Green Flag highlighted the dangers of millions of drivers delaying an MOT.
It cited Government test data showing that of the 37 million cars and vans licensed in Britain, nearly a third fail their initial MOT with more than a fifth having a major defect.
A survey of 2,019 drivers suggested that 9% never conduct safety checks on their vehicles, with a further 27% only doing so once a year.
A fifth (20%) of respondents admitted to driving a car that was not roadworthy, rising to 38% for those aged 18-34.
Department for Transport (DfT) figures show that 39 people were killed and 378 seriously injured on Britain’s roads in crashes where a vehicle defect was a contributory factor in 2018.
Brake director of campaigns Joshua Harris stressed the importance of regular safety checks of vehicles.
“Even minor defects, like a worn wiper blade, can play a part in a catastrophic crash,” he said.
“Drivers have a responsibility for a vehicle’s safety and this is a responsibility which should not be taken lightly.
“We urge all drivers to perform regular walk-round checks of their vehicle, once a week and before any long journeys.
“It is a couple of minutes which could be the difference between life and death.”
A DfT spokeswoman said: “The MOT exemption was introduced to help stop the spread of coronavirus. Drivers, by law, must ensure their vehicle is roadworthy at all times and the DVSA has issued guidance to drivers on how to keep a car safe.
“Garages have been allowed to remain open throughout the pandemic to ensure cars can be fixed and maintained.”