Back-seat driving is rife in Britain according to new research, leading to millions of motorists having avoidable accidents.

The research, released by insurance comparison website Confused.com, shows that two thirds (66%) of British motorists have been`victims' of back-seat drivers, and almost one in four (24%) have been in an accident whilst dealing with distractions from other passengers.

These distractions mean that 20% of British motorists will have to fork out up to £500 over their driving lives to repair accidental damages `caused' by back-seat drivers.

The most common professions for back seat pests are bus drivers, train drivers and delivery men. On the other hand, teachers are the most patient of passengers.

Most motorists confess that they would rather journey with colleagues than loved ones. Partners are the worst back seat drivers, with husbands and boyfriends disrupting the driver most often and 45% of them voicing their traffic-tips several times during the shortest of journeys.

Particularly bad at knowing when to keep quiet are parents, who feature second on the list of frequent offenders (28%) when it comes to interfering from the back seat.

A new back-seat driving etiquette guide from etiquette experts Debretts, however, offers advice on how to be the perfect passenger for family and friends.

Gareth Kloet, Head of Car Insurance at Confused.com, said: "It's never been more important for drivers to keep their costs as low as possible. Our research shows that having other people in the car can distract us from the road, and lead to accidents, which in turn increases the cost of our car insurance policies."

Debrett's spokesperson, Jo Bryant, added: "If you're a passenger in someone else's car your behaviour must be polite at all times, just as it would be if you were visiting their home. The Etiquette Guide for Back Seat drivers will ensure that every journey is courteous and civilised."

Back-seat drivers can find Debretts' advice at: http://www.confused.com/car-insurance/articles/driving-tips-etiquette-rules-for-back-seat-drivers

But if that doesn't work, visit http://www.confused.com/car-insurance/articles/comebacks-to-silence-back-seat-drivers for a selection of witty comebacks to help deal with the frustration of back-seat badgerers.