Drivers in Britain are throwing away hundreds of millions of pounds every year by making one simple mistake with their cars that takes just a matter of minutes to rectify, according to a new study.

Motorists driving with under-inflated tyres are said to be wasting at least £112million annually by burning through rubber more quickly - and are also avoidably increasing their fuel bills in the process, according to The Motor Ombudsman.

The British Tyre Manufacturers’ Association (BTMA) and charity TyreSafe estimate that 57 per cent of cars in the UK have tyre pressures at 10 per cent less than what is recommended by vehicle manufacturers. 

With around 33million motors on the road, this equates to around 19million with underperforming rubber. 

The most common tyre size for cars in the UK is 16 inches. On average, the cost to replace one is £85, says the BTMA.

Drivers failing to check if tyres are pumped up to the manufacturer's recommended pressures is said to be equating to a preventable annual loss of 1.3 million tyres, the ombudsman says.

With Britons said to be burning through rubber much quicker than they should be, the bill for accelerated tyre wear is at least a whopping £112m per year.

And that's if just one tyre is under inflated; if every corner of the car is below the suggested pressure, it could be costing motorists four times as much in prematurely destroyed rubber.

There is also the additional financial drain on fuel economy.

Under-inflated tyres ultimately increase rolling resistance and therefore puts an extra demand on your car's engine. The result is that it will need to work harder when you accelerate. 

Philip Gomm, spokesman at road safety charity the RAC Foundation, explains: 'Incorrectly inflated tyres can be bad for safety, but also have an impact on fuel efficiency.

'If they are under-inflated fuel economy is cut by as much as ten per cent because of the extra resistance with the road.'

For a petrol family car returning 40 miles per gallon (mpg), the annual fuel cost (based on the current price of unleaded at 146.4p, according to RAC Fuel Watch) to cover the national average of 7,400 miles per year is £1,231.

But with underinflated tyres reducing fuel efficiency by up to 10 per cent, this slashes economy to 36mpg and would see an annual fuel bill rise by £137 to £1,368, based on This is Money's calculations.

Continental Tyres estimates every 4.3 PSI (Pounds per Square Inch) below the recommended pressure results in an additional 1.5 per cent use of fuel.

One of the main reasons why drivers are making this mistake is because more than a third don't feel confident inflating their tyres.

Shockingly, some 37 per cent of respondents to a 1,000-strong driver poll said they're unsure how to pump air into their tyres - and over half (51 per cent) don't know how to correctly measure tread depth to ensure the rubber is above the 1.6mm minimum legal requirement.

Bill Fennell, Chief Ombudsman, said: 'Under-inflated tyres carry a number of risks and costs. 

'Avoiding any unnecessary expense is especially pertinent with the current financial pressures on the nation’s motorists.'

Stuart Lovatt, chair at TyreSafe, added: 'Under-inflation compromises tyre and vehicle performance, and can ultimately cost drivers and vehicle owners dearly, as The Motor Ombudsman study has clearly shown. 

'We strongly urge motorists to observe the pressure levels recommended by vehicle manufacturers. This is because, they have been calculated with absolute precision to ultimately keep vehicle users safe when on the road.'

Four quick tyre pressure tips for drivers

1. How often should you check tyre pressure?

Ideally check your tyre pressures at least once a month and before making long journeys or carrying heavy loads, making sure to remember to check the spare tyre should you carry one.

2. Where do I find the correct tyre pressures for my vehicle? 

The correct tyre pressures for your car can usually be found on a sticker on the driver’s door frame (when the door is open), inside the fuel filler flap or in the owner’s manual if no sticker is present.

3. Check pressures before a journey when the tyres are cold 

If you can, check your tyres whilst they are cold.

4. Carry out other tyre maintenance at the same time as checking pressures 

When checking your tyres, also look for any splits, tears or ‘bumps’ in both the sidewall and the treaded area. If there are any signs of damage, have the tyres inspected at a garage and replaced if necessary.

5. Is there enough tread on the tyres? 

Ensure that you have at least 1.6mm of tread depth across the whole width of the tyre. This is simple to check using a 20p piece by putting the coin into the tyre groove. If the outer band of the coin is not visible, your tyres are legal. But if you can see the band, they’re likely illegal and need replacing.