Who has right of way when two sailing boats are on opposite tacks?
B · Beginner · When boats meet · 5 of 5When boats are on opposite tacks, the one on port tack must keep clear of the one on starboard tack. A boat is on starboard tack when the wind comes over its right-hand side, so its sails are out to the left. This is the first rule most sailors learn.
How it works
- Which tack: a boat is on the tack, starboard or port, that matches its windward side. Windward is the side the wind is coming from, the side opposite the mainsail.
- The rule: "When boats are on opposite tacks, a port-tack boat shall keep clear of a starboard-tack boat."
- What keeping clear means: the right-of-way boat can sail its course with no need to take avoiding action.
- How the port-tack boat does it: it may pass behind the other boat, tack before reaching it or cross ahead if it can do so without making the other boat alter course.
- A limit on the starboard-tack boat: on a beat to windward, when a port-tack boat is keeping clear by passing behind, the starboard-tack boat shall not bear away if that forces the port-tack boat to change course immediately to keep clear.
- The shout: crews often call "Starboard!". The rules do not require the call.
The glossary explains the two tacks under port and starboard tack.
Tricky cases
The port-tack boat crossed ahead and the starboard-tack boat had to turn slightly to miss it. Was that a breach?
Yes. The port-tack boat keeps clear only if the other can sail its course with no need to take avoiding action.
Does the starboard-tack boat have to shout "Starboard"?
No. The rule applies whether or not anything is said.
Can the starboard-tack boat turn towards the port-tack boat to catch it out?
No, not freely. When a right-of-way boat changes course it must give the other boat room to keep clear.
Does starboard tack always win at a mark?
No. Mark-room and the rule on tacking inside the zone can change who must give way there.
Why the rule exists
Two boats converging at speed need to know in an instant which one gives way. The tack a boat is on can be read from across the water by the side its sail is on. The same convention is used at sea outside racing, which is general knowledge and not stated in the racing rules.
Where it differs
| Where | What changes | Source |
|---|---|---|
| Racing Rules of Sailing | As above | RRS 10; RRS 16; RRS Definitions (Keep Clear; Tack, Starboard or Port) |
| Meeting a vessel that is not racing | The collision regulations for all shipping apply | RRS Part 2 preamble |
| If the notice of race says so | The collision regulations replace these rules altogether, as often at night offshore | RRS Part 2 preamble; C for "at night offshore" |
From the rule book
World Sailing The Racing Rules of Sailing 2025-2028, rules 10 and 16, the preamble to Part 2 and the Definitions (Keep Clear; Leeward and Windward; Tack, Starboard or Port). In force from 1 January 2025. Checked 14 October 2026. Official document: The Racing Rules of Sailing 2025-2028 (PDF).