A survey of driving behaviour put together jointly by Moto Hospitality and BSM found that only 1% of motorists were annoyed by drivers making calls at the wheel.
This means that about 45 of the 4,500 drivers questioned had a problem with motorists using phones while driving.
The Royal Society for the Prevention of Accidents says there have been at least 17 deaths on Britain's roads where mobile phones have been implicated.
Tim Moss, Moto managing director, called on employers to lead by example and discourage drivers from answering calls at the wheel. He said: 'We understand that people are under pressure to keep in contract by using a mobile phone but we would encourage drivers to leave their phones on voicemail and take a break to pick up messages.'