The Different Types of Boat Flags & What They Mean

The Different Types of Boat Flags & What They Mean

When you are out on the open water, it’s easy to assume that no dangerous accidents will occur. However, accidents can happen within a blink of an eye, and in the water, this can induce a helpless feeling. If disaster strikes, you should have boat flags you can fly to relay a message to passersby or first responders. These are the different types of boat flags and what they mean.


Nautical flags come in three shapes, with the square being the most common of the trio. The other two are triangular, with pendant flags having a flat tip at the end. There are 26 square flags for the alphabet and 10 pendants for numbers 0 through 9. If a number is greater than 9, a boat would have to combine flags to get the complete message across.


Each of the 26 square flags has a meaning behind each letter. Considering how challenging it is to verbally communicate in a naval emergency, these flags help relay a message of the situation at hand:

  • A (Alpha) – Diver down
  • B (Bravo) – Carrying dangerous cargo
  • C (Charlie) – Yes (Confirmation)
  • D (Delta) – Steer clear
  • E (Echo) – Shifting course
  • F (Foxtrot) – I am incapacitated
  • G (Golf) – In need of a pilot
  • H (Hotel) – There’s a pilot on board
  • I (India) – Heading to port
  • J (Juliet) – Fire on the vessel
  • K (Kilo) – I want to communicate with you
  • L (Lima) – Stop the vessel instantly
  • M (Mike) – The vessel has halted
  • N (November) – No (Confirmation)
  • O (Oscar) – Person overboard
  • P (Papa) – About to set sail
  • Q (Quebec) – Requesting free pratique
  • R (Romeo) – Reversing course
  • S (Sierra) – My engines are going astern
  • T (Tango) – Steer clear and don’t pass
  • U (Uniform) – Danger ahead
  • V (Victor) – I need assistance
  • W (Whiskey) I require medical assistance
  • X (X-Ray) – Stop
  • Y (Yankee) – I am dragging anchor
  • Z (Zulu) – In need of a tug


Your flags must be easily visible, so you will only see five colors: red, black, blue, yellow, and white. Therefore, there isn’t a lot of variety for colors for nautical flags. Some flags are completely solid, whereas others might have a combination of the five colors. However, you won’t find any other colors onboard.


Relaying messages to emergency responders can help you escape from a perilous situation. Using different colored flags, you can communicate exactly what is going on. You can effectively describe the ongoing crisis with either one or multiple flags. It can be as simple as displaying a “U” flag to signify that there is danger ahead, or as intricate as a combination of “M,” “O,” and “W” flags to state that you have stopped because there is someone overboard and you need medical assistance.

Now that you know about the different types of boat flags and what they mean, you’ll need some marine flag poles to put them in. Check out our store at Innovative Marine Group to purchase those flag poles, as well as any other marine gear that you might need.

Back to blog