Depending on where you are in the US and the world, trailer lights used to tow boats on land must carefully adhere to specific standards. Governed by the DOT and other national organizations, such guidelines pertain to the type of boat trailer lights and placement of the units.
Size and Weight
In most cases, the size of the trailer will dictate various lighting requirements for federal compliance. Furthermore, the weight of the trailer is also a key factor in determining the types of luminaries used on the trailer. An example of this is the ruling for trailers that are 80” wide (minimum) with a GVWR of more than 10,000 lbs. Such massive trailers must have reflectors (red/white) or reflective tape at the side and rear of the unit. It is important to note that weight limitations for boat trailers vary from state to state.
Smaller trailers do not need as many lights, compared to large variants. For instance, boat trailers less than 30” wide must have a brake light, tail light and reflector (rear), which should all be secured at the center of the unit.
Types of Trailer Boat Lights
At a very basic level, almost all trailers used for hauling boats should be equipped with stop/breaking lights, tail lights, turn/signal lights and reflectors. Moreover, the color of the lights must be carefully selected. Tail lights, stop lights, rear reflectors and side marker lights are typically red, while rear turn signal lights, front side marker lights and front side reflectors can be yellow. Lights for illuminating license plates are the only exception, with white being the color of choice for increased clarity.
For large boat trailers (over 80” wide and with a GVWR of 10,000+ lbs.), white light is applicable to marking the rear, upper body of the unit, as well as the bumper bar and rear, lower body.