Motorists are wasting up to £174 million a year by failing to drive a hard enough bargain over car finance.
That is the message from uSwitch.com, a price comparison website, which has found that people will often fail to properly research the cheapest loan option when buying a new car.
All dealerships offer their own finance deals and often customers will opt for these as they are more convenient.
But uSwitch.com has found that buyers could waste up to £1,094 in unnecessary interest payments by not shopping around for a better deal.
"Brand new cars are already a big expense but consumers can unwittingly inflate the purchase price by up to £1,100 by choosing the wrong finance deal," said Mike Naylor, heads of personal finance at uSwitch.com.
"However, there is a simple win-win solution. Finding a competitive loan and having the money ready to buy the car immediately will not only ensure that people get cheaper finance but it also gives them more bargaining power to get the best purchase price."
There were more than 2.4 million new cars purchased in Britain last year. A further 224,644 are expected to be sold in March when the new registrations are released.