Starting on Nov. 27, you can drive through 3.5 million holiday lights at the New Hampshire Motor Speedway in Loudon. But this is about as close as you can get to putting Christmas lights actually on your car in the state.
That’s because New Hampshire laws regulate the color and types of lights can be displayed on vehicles. For example, blue colored lights on a car are restricted for use by law enforcement, the State Department of Corrections and emergency response, while red lights are restricted to police, fire and rescue vehicles.
There are no laws specifically prohibiting people from decorating their car in other ways for Christmas. However, you must follow all safety and legal guidelines.
More: How early is too early to put up Christmas lights? What New Hampshire laws say
Here’s what to know.
Driving with lit Christmas lights on your car violates vehicle lighting laws in New Hampshire.
Under New Hampshire law, only authorized emergency vehicles, like law enforcement, fire and emergency medical services vehicles may be equipped with flashing lights.
Colored lights are also regulated: only certain vehicles can use blue, red, green, amber or purple warning lights.
There are many car decorations available for Christmastime, like reindeer antlers and Rudolph noses.
In general, you can decorate your car as long as you follow safety and legal regulations.
This means any decorations must not obstruct your license plate, headlamps or car windows, as doing any of these things is illegal in New Hampshire. 
You should also make sure that any decorations are securely fastened so that they don’t become a hazard to other drivers or harm your own car, Toyota suggests.

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