The number of motorists admitting they take phone calls and send text messages while driving has tripled in a year, according to an RAC survey.
As many as 39% of drivers admit to being distracted by calls, texts and social media website alerts on their mobile phones while at the wheel.
Those saying they take calls while driving has risen from 8% to 28%, while those admitting texting at the wheel has increased from 11% to 31%, the poll of 1,150 British motorists found.
The survey also showed that on an average car journey of 23 minutes, a motorist's phone rings or beeps at least once.
Just over half (53%) of motorists admit they are likely to take their eyes of the road to see who a call is from and 45% admit they would look to see who a text is from.
Young drivers (17 to 24 year olds) are most likely to glance at a phone while driving if it rings or beeps, with 58% saying they would.
As many as 21% of motorists admit they are likely to check a social media alert from applications such as Facebook and Twitter while driving.
The top five social media sites and applications which motorists admitted using while on the road (stationary with the engine running or driving) are, in order: email, Google Maps, music, photos and Facebook.
Almost half (46%) of all motorists who receive calls when they are driving claim not to be distracted by them, and 47% believe texting on the road does not divert their attention from driving.
Many motorists think it is permissible to use mobile phones while driving when the car is not moving. Over a quarter (26%) believe it is acceptable to use phones (for calling, texting and social media) at traffic lights, 33% believe using a phone in a lay-by is permissible and 9% say using phones while stuck in traffic is reasonable.
RAC motoring strategist Adrian Tink said: "It's extremely concerning that the use of mobile phones for texting and calling has risen in the past year. It is also worrying that people are admitting to using their phone for a whole host of social media applications while driving.
"Taking your eye off the road, just for a second, to read an alert or check who a call came from can have potentially fatal results. This steep rise in mobile phone usage at the wheel could potentially be set to continue as more and more people embrace smart phone technology."
Peter Rodger, chief examiner of the IAM (Institute of Advanced Motorists), said: "These results are worrying, particularly the rise in the use of social media applications, and the high level of young drivers admitting glancing at the phone if it rings or beeps.
"Young drivers are the least experienced on the road, and the most at risk of having an accident, so anything that distracts them further is a real issue.
"The growing range of technology is increasingly intruding into the driving environment, and using mobile phones in the car needs to be subject to tougher enforcement."