Port is the left-hand side of a boat when you are on board facing forward, towards the bow. The word is fixed to the boat, not to you: the port side stays the port side whether you are looking forward, aft or over your shoulder, which is exactly why sailors use it instead of “left”. Beginners need to remember that port is left and shows a red light. Experienced sailors know that port is also a harbour (“making port”), an opening in the hull (a port light or porthole), and the deciding word in the most common right-of-way situation in sailing: a boat on port tack keeps clear of one on starboard tack.
Remembering port and starboard
Everyone has a mnemonic. “Port” and “left” both have four letters. Port wine is red, and the port sidelight is red. “There is no red port left in the bottle” covers colour and side in one line. Whichever you use, use it until it is no longer needed, because in a crossing situation at night you will not have time to think about it.
The word replaced the older “larboard” in the nineteenth century because “larboard” and “starboard” sounded too alike when shouted into a gale. Starboard comes from the steering board, the oar that early ships carried over the right-hand quarter; with the steering oar to starboard, a ship came alongside a quay on her other side, the side facing the port, and the name stuck.
Lights, rules and the port side
Under the International Regulations for Preventing Collisions at Sea (COLREGS), a vessel under way at night shows a red sidelight on the port side and a green one on starboard, each visible through an arc of 112.5° from dead ahead to just abaft the beam. If you see a red light ahead on a converging course, you are looking at another vessel’s port side and she is crossing from your starboard: you are the give-way vessel. Small sailing yachts often combine both sidelights and the stern light in a single masthead tricolour, which is permitted only for sailing vessels under 20 metres and only when under sail alone.
Port also decides the give-way rule between sailing boats. COLREGS Rule 12 and Racing Rule 10 both say that when two boats are on different tacks, the one with the wind on her port side keeps clear of the one with the wind on her starboard side. Whether you are cruising or racing, “port keeps clear of starboard” is the rule you will use most often.
Port in sail handling and trim
Everything on the boat is named by side. The port sheet, the port winch, the port jib track and the port runner are the ones on the left of the centreline, and a helm’s instruction to “ease the port sheet” or “trim the port guy” should never need a second thought. On a symmetric spinnaker the port guy holds the pole end when the pole is to port, and the port sheet trims the clew when the pole is to starboard. Learning to think in port and starboard rather than left and right removes a whole class of mistakes during gybes and sail changes when crew are facing in every direction.
Other meanings of port
- A harbour or haven: to make port, port of entry, port authority. The word comes from the Latin portus, a harbour.
- Port hand mark: in IALA Region A (Europe and most of the world) a red can buoy that you leave to port when entering from seaward; in Region B (the Americas, Japan, Korea and the Philippines) the port hand mark is green.
Cruising and racing perspectives
For cruisers, port matters most at night and in traffic: know your own lights, know what a red light on the bow means, and remember that the buoyage colours change between IALA regions. For racers, the port and starboard distinction is tactical currency. A boat on port tack approaching a starboard-tack fleet must duck, tack or find a gap; a starboard-tack boat holds the right of way and can use it to force others about. Whole start-line strategies are built around which end is favoured and who will be on port.
Frequently Asked Questions about Port
Which side is port, left or right?
Port is the left side of the boat when you face the bow. It stays the left side of the boat regardless of which way you happen to be looking.
What colour is the port light?
Red. The starboard light is green, and both are visible over an arc of 112.5° from dead ahead to 22.5° abaft the beam.
Why is it called port and not larboard?
Larboard was replaced in the 1800s because it was too easily confused with starboard when shouted. Port was chosen because a ship with her steering oar to starboard came alongside a harbour, or port, on her left side.
Port is one of the first words a sailor learns and one that never stops mattering. It tells you which light you are looking at, who gives way, which sheet to ease and which buoy to leave to which side. Learn it so well that you never have to translate it from “left”, and half the confusion on a busy deck disappears.