What color is the sidelight on the port side?

The sidelight on the port side of a vessel is red. This is a standardized color that helps to identify the direction a boat is facing when under way. According to the International Regulations for Preventing Collisions at Sea (COLREGs), vessels are required to display specific colored lights to indicate their position and course to other vessels.

The use of colored sidelights—red for the port side and green for the starboard side—facilitates safe navigation, particularly at night or in reduced visibility. This color distinction allows other boaters to ascertain which side of the vessel they are observing and to understand its direction of travel. The red sidelight on the port side must be visible from a distance of at least 112.5 degrees off the bow, further aiding in situational awareness on the water.