One in ten older drivers think the speed limit for cars on UK motorways is 80mph, according to research from the AA Charitable Trust.

Overall, 8% of drivers (equivalent to more than 250,000 drivers) got the motorway speed limit incorrect with 7% thinking it was 80mph and 1% thinking it was 60mph. Men (9%) were twice as likely as women (4%) to incorrectly say the speed limit for cars on UK motorways is 80mph

Drivers in Scotland and the North East (9%) were most likely to incorrectly say the national speed limit for cars on a motorway is 80mph.

The results come from an AA/Populus poll of 22,827 motorists who were asked what they thought the national speed limit for cars and van derived cars was on various types of roads.

Younger drivers proved themselves far more aware of what speed limits are than older drivers:

• 95% of 18-24-year-olds correctly said speed limit was 70mph on motorways compared to 89% of over-65s.

• 74% 18-24-year-olds correctly said speed limit was 70mph on dual carriageways compared to 64% of over-65s.

• 74% 18-24-year-olds correctly said speed limit was 60mph on single carriageways compared to 59% of over-65s.

The only speed limit over-65s knew better than 18-24-year-olds was correctly identifying 30mph as the limit in a built-up area with street lamps. However, although fewer 18-24-year-olds correctly identified this (93%) they erred on the side of caution with one in twenty (6%) saying they would assume the limit to be 20mph.

And four out of ten drivers could not identify the correct speed limit for a dual carriageway.

Regional figures showed nearly half of drivers in the North West (47%) and four out of ten (40%) Londoners do not know what the speed limit on a single carriageway is. Drivers in the East of England were most likely to correctly identify 60mph as the national speed limit for cars or car-derived vans on a single carriageway.

Edmund King, director of the AA Charitable Trust, said: “It is astonishing that 250,000 qualified drivers don’t seem to know the motorway speed limit is 70mph. Some confusion about the motorway speed limit for cars could well be down to the previous Transport Secretary floating the idea of raising the limit to 80mph.

“There is no reason why drivers shouldn’t be able to correctly identify the speed limit of dual carriageways and single carriageways.

“The lack of knowledge around limits just highlights the importance of keeping your driving skills up to date. This follows a previous AA study that showed that some 17 million drivers would struggle retaking their driving test.