MOTORISTS are counting the cost of failing to belt up in their vehicles after new figures showed a 30 per cent rise in the offence over the past three years.

More than £3.5 million worth of fixed penalties have been given out to drivers as 35,000 people were caught breaking the law by not wearing seat belts in 2013.

The figure represents a rise of 8,000 on the number caught in 2010 as research shows that one in five UK motorists stopped for seat belt offences are from Scotland.

The rate of increase in Scotland is nearly double that for the whole of the UK. Motoring organisations believe the difference may be down to better police enforcement north of the Border.

Data published by the car insurance wing of LV=, formerly Liverpool Victoria, showed that across the UK there were 180,000 fixed penalty notices issued for seat belt offences in 2013 - a 17 per cent increase on the figure for 2009.

In the first seven months of this year in the UK, more than 80,000 drivers have been stopped by police and had been charged a total of £8.2 million in fines for seat belt offences - the current penalty for not wearing a seat belt is £100.

It has also emerged that nearly 12,000 of those were in Scotland.

An RAC spokeswoman said: "It's frightening to think so many people are still not wearing something that has proved time and again to save lives.

"And the fact the number actually increased dramatically last year in Scotland beggars belief. It must be down to police enforcement.

"In reality, it is unlikely to be a change in behaviour. For most of us it is automatic to put your seat belt on."

The RAC said that since it was made law to wear seat belts in 1983 the number of lives lost on the road has decreased dramatically. This is despite there being 14 million more vehicles on our roads than 30 years ago.

When the law came into force, the Department for Transport said 30,000 people a year were killed or serious injured in road accidents. The Government hoped the compulsory wearing of front seat belts would save 1,000 lives a year as evidence at the time suggested that six out of ten drivers ignored the advice to belt up in the front.

Since then the RAC say the number of deaths in vehicles has fallen to an all-time low.

RAC analysis of 30 years of Department for Transport road casualty statistics showed that when the seat belt law was brought in 2,245 people lost their lives in vehicles per year while 28,331 were seriously injured.

But in 2012, fatalities had fallen to 888, a 60 per cent reduction on 1,357 since 1983, and serious injuries are down to 9,258, a 67 per cent reduction of 19,073.

LV= also released details of a survey of 2,016 adults - including 1,578 drivers - which showed that:

l 6 per cent of drivers do not wear a seat belt when driving and 9 per cent do not wear one when they are a front-seat passenger;

l 47 per cent of motorists were unaware they can be fined for not wearing a seat belt;

l 24 per cent of drivers do not always wear a belt when sitting in the back;

l 42 per cent of drivers do not belt up when travelling by taxi.

The survey showed that among those not wearing belts, older drivers said they were too restricting, while younger ones said they sometimes did not comply on short journeys

But LV= said Government figures showed that 19 per cent of people killed in car accidents last year were not wearing seat belts. It added that of these, safety experts estimated that 50 per cent would have survived if they had been restrained.

Police Scotland were unavailable for comment.