U.S. running light standards conform closely to the international COLREGS (collision regulations). Called the Inland Navigation Rules or Unified Rules, the U.S. regulations require all boats built after December 24, 1981, to be in compliance. No retrofit is necessary on boats built before this date if they are in compliance with previous inland rules. However, in international waters, these boats would not be in compliance with the COLREGS and could be deemed liable in an accident.

VISIBILITY OF RUNNING LIGHTS

Vessels Under 39.4' (12 Meters)

• White/Red/Green or Yellow 360° - 2 n.m.
• Masthead - 2 n.m.
• Stern - 2 n.m.
• Red/Green - 1 n.m.
• Towing - 2 n.m. Vessels 39.4-65.6' (12-20 Meters)
• White/Red/Green or Yellow 360° - 2 n.m.
• Masthead - 3 n.m. • Stern - 2 n.m.
• Red/Green - 2 n.m.
• Towing - 2 n.m.

Boats under 23' may carry a 360° lantern or flashlight in lieu of running lights. Also, international regulations allow sailboats under 65' (20 meters) to display a single masthead tricolor navigation light while under sail.