Decorating your car with Christmas decorations could end up costing you thousands.
Drivers can buy anything from reindeer antlers, Santa stickers and huge Santa hats for their cars.
But these festive accessories could be classed as a "modification", reports the Mirror .
Research from Zero Deposit Car Leasing found that unless the decorations are declared, they could invalidate your insurance cover.
This means that drivers would be liable to pay for damage in the event of an accident.
Tom Preston, Zero Deposit Car Leasing managing director, told the Mirror: “Thousands of motorists use car decorations to bring a touch of festive cheer to the roads.
"Yet, our research shows modifying your vehicle with something as simple as a Christmas sticker could invalidate your insurance if it’s not declared.
"Drivers who want to get into the spirit of the season on their daily commutes, by transforming their car into Rudolph the Red Nose Renault, should probably think again if they want to avoid having a blue Christmas this year. Bah humbug, indeed.”
A study from General Motors also found that adding antlers and a nose to your car can add to your petrol bill.
It calculated they add as much as a 3% increase to a car's drag coefficient - meaning your efficiency drops by one mile per gallon.
And drivers thinking that a festive ornament on the dashboard won't harm their insurance should think again.
The Highway Code and the Road Traffic Act states that a driver is not allowed to use a vehicle if the view of the road is obstructed "in any way".
Drivers could face a £100 fine, rising to £1,000 and three points, if the dispute goes to court.
