Where are the side lights located on a vessel?

• A. Green on starboard side; Red on port side.
• B. Green on port side; Red on starboard side.
• C. White on starboard; White on port.
• D. Yellow on both sides.

Answer: (A)

Side lights tell other vessels which side of your boat you’re on. The left (port) side uses a red light, and the right (starboard) side uses a green light. They’re mounted toward the bow so each color is visible along the side to approaching vessels, making it clear whether you’re on a crossing course or not. This standard setup—red on port, green on starboard—helps other boats quickly interpret your orientation, especially at night or in poor visibility. White lights serve other purposes (like forward or stern visibility) and aren’t used for indicating the sides.