Sailing Flags & Their Meanings

Sailing flags, or nautical flags, are a way for ships to communicate with one another on the water without using radios. They are a component of INTERCO, the international code of symbols. Maritime flags exist to represent the 26 letters of the Latin alphabet, A to Z and the numerals 1 to 9, along with 22 other flags to indicate a ship's status and communicate details such as direction and speed. Most nautical flags have more than one meaning, which can generally be determined in context. All lettered flags have standard meanings along with the letter they represent.

  1. Different Meanings

    • Sailing flags' meanings differ, depending on where they are raised, the vessel that's waving the flag and the context in which the flag is raised.

      For example, some flags take on different meanings during yacht and dinghy races. The "P" flag, when raised by a fishing boat, means the nets are tangled with the bottom of the sea; when racing, this same flag signals the race is about to begin. Similarly, when racing, the "L" flag indicates instructions to follow; otherwise, it is a warning to immediately stop a ship.

    Letters

    • Twenty-six of INTERCO's nautical flags represent the letters of the Latin alphabet, and they are indicated verbally using the NATO phonetic alphabet (alpha, bravo, charlie, delta, etc.). All of the alphabetic flags are square in shape except A and B, which are pentagonal.

      Alphabetic flags come in five colors: white, black, blue, yellow and red. Except for the I ("India") flag, which is yellow with a black circle in the center, all of the flags are comprised solely of designs using straight lines (crosses, checks and stripes).

      Q is the only flag that is monochromatic; it is a solid yellow square.

    Numerals

    • There are two types of numeric flags: allied flags, which are square and resemble alphabetic flags, and pennant flags, which are triangular. Today, allied numeric flags are considered outdated, aside from in the U.S. Navy. Generally, pennant flags are widely used to represent numbers.

      Like alphabetic flags, numeric flags display only the five main colors of white, black, blue, yellow and red. The numbers 1 and 2 contain a circular shape in the middle; otherwise, patterns of numeric flags are strictly in straight lines.

      Numeric flags do not have any other common meanings other than the numbers they represent.

    Other Flags

    • Aside from the numbers 1 through 9 and the Latin alphabet, there are 22 other official flags used to communicate between ships.

      These includes flags to represent the words "port" and "starboard" (the right and left sides of a ship's hull); flags to indicate that a ship is turning; and flags used to mark racing courses.

    Flag Combinations

    • When two or more alphabetic or numeric flags are combined, they take on different meanings.

      A string of alphabetic flags often spell out a word, but two alphabetic flags can mean a number of things, such as:

      AC: I am abandoning my vessel.
      GW: We have a man overboard; please help with rescue.
      NC: Distress.
      V plus numerals: Speed in kilometers per hour.
      DV: I am drifting.
      PP: Stay clear of my ship.