Nautical Flags Meaning & Alphabet

Nautical Flags Meaning & Alphabet

Learning how to sail requires learning a few key visual signals. Understanding what the nautical flags mean will increase your ability to navigate safely in any body of water. They are also constantly used during sailing regattas or races.

Nautical flags are alphabet flags and numeral pennants that you learn in the United States and are the same as the boating signals used in Canada, Europe and the rest of the world.

These visual signals have been internationally recognized and standardized over the last 300 years.

Each letter represents a specific scenario that indicates either a need for help or a request of some sort. They can also inform other vessels on the water of a particular action with the explicit expectation of giving space.

International Maritime Signal Flags Sea Alphabet , Vector Illu

Solo and Combined Flags

Boats can display between 1 and 7 nautical flags. Combining Oscar and Whiskey flags, indicates “Man overboard. I require medical assistance”.

2 nautical flags together usually indicate a problem or hazard, requesting either assistance or a wide birth. Three or more flags can signal compass points, location coordinates, names and often include pennants.

Mast Of An Ancient Sailing Vessel
Mast of an ancient sailing vessel

The Nautical Alphabet

Talking over VHF can be tricky to hear depending on the squelch, distance and quality of the radio unit. Using the nautical alphabet to spell out names is used by the military as much as it is by recreational boaters.

It’s often used to provide a license plate because it’s easier to understand over the air too.


The following indicates a specific maritime scenario for each of the 26 letters of the alphabet:

A: Alpha – diver in water; speed trial underway

B: Bravo – dangerous cargo

C: Charlie – yes (affirmative); change of course (sailing regatta)

D: Delta – stay clear, I am maneuvering with difficulty

E: Echo – altering course to starboard

F: Foxtrot – I am disabled, communicate with me; operations underway (navy carriers)

G: Golf – I need a pilot

H: Hotel – pilot on board

I: India – I am altering my course to port

J: Juliet – vessel on fire, stay clear

K: Kilo – I want to communicate with you

L: Lima – stop your vessel instantly, I have something important to communicate; Come Within Hail or Follow Me (Sailing Regatta)

M: Mike – my vessel is stopped and making no way through the water; Mark Missing (Sailing Regatta)

N: November – no (negative); Abandonment and Re-sail (Sailing Regatta)

O: Oscar – Man overboard

P: Papa – In port: All personnel return to ship; vessel is about to sail; Race is about to start (Sailing Regatta); At sea: It may be used by fishing vessels to mean: “My nets have come fast upon an obstruction”

Q: Quebec – I request admission into port

R: Romeo – reverse course

S: Sierra – engines are moving astern

T: Tango – Keep clear; engaged in trawling. (International); Do not pass ahead of me. (Navy)

U: Uniform – you are heading into danger

V: Victor – require assistance

W: Whiskey – I require medical assistance

X: X-ray – stop your signally and watch for my message

Y: Yankee – I am dragging anchor

Z: Zulu – I require a tug

What You Make of Them

Like all languages, there is a basic use that is universally understood and there is a more context-based usage too. Like idiomatic or slang use, different groups in specific situations have customary practices.

There are 3 types of dialects for nautical flags: recreational, regatta and navy. Recreational flags can be bought online or at sailing clubs and associations.

For example, notice in the alphabet list above that there are additional meanings used in racing contexts. There are often combinations of flags used for sailing regattas to indicate the progress of a race, when it is to begin, etc.

The Papa signal, for example, indicates that a race is about to begin. Sierra indicates that a race has been shortened.

Like for racing naval ships can use flags in secret ways to openly communicate without an adversary understanding intent. This makes nautical flags the building blocks of code in this scenario.

Nautical Flags On A Blue Sky (098)

Do you need to know the Nautical Flags?

In this day and age of electronic chart plotters and humble coastal sailing, learning the alphabet is not strictly required. Even during a good keelboat course where you learn to sail, learning the nautical flags isn’t required. Most recreational boats are furnished with different forms of communication and navigation instruments.

But what happens when there’s no cell signal or your power fails?

Like visual signals, audio communication using horns also helps ships understand each other’s position and intent. It’s a way to avoid collisions and call for help.

Familiarity with the most important signals is part and parcel of a good sailing and boating course and will increase your confidence and the safety of your crew at sea.


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Frequently asked questions

What are nautical flags?

Nautical flags are visual symbols used at sea to communicate with other vessels. They are internationally recognized–they are universal all over the world–and have been standardized over the last 300 years, mainly by European and American navies.

These flags include alphabetic flags that have specific meanings and numerical pennants that describe specific locations or names.

Learn more about the meaning of Nautical Flags in our guide.

What do nautical flags mean?

Nautical flags include alphabetic flags that have specific meanings and numerical pennants that describe specific locations or names.

Learn more about the meaning of Nautical Flags in our guide.


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