ICAO Phonetic Alphabet
The NATO/ICAO standard alphabet used worldwide in aviation radio communications, per ICAO Annex 10 and Doc 9835.
Last reviewed: March 2026
The ICAO phonetic alphabet (formally the NATO Phonetic Alphabet) was standardised to ensure clear radio communication between pilots and ATC regardless of language barriers. Each word was specifically chosen to be phonetically distinct across all major languages.
The Complete Alphabet
| Letter | Word | Pronunciation | Notes |
|---|---|---|---|
| A | Alpha | AL-fah | Stressed on first syllable |
| B | Bravo | BRAH-voh | |
| C | Charlie | CHAR-lee | |
| D | Delta | DELL-tah | |
| E | Echo | ECK-oh | |
| F | Foxtrot | FOKS-trot | |
| G | Golf | GOLF | |
| H | Hotel | hoh-TELL | Stressed on second syllable |
| I | India | IN-dee-ah | |
| J | Juliet | JEW-lee-ETT | |
| K | Kilo | KEY-loh | |
| L | Lima | LEE-mah | |
| M | Mike | MIKE | |
| N | November | no-VEM-ber | |
| O | Oscar | OSS-kah | |
| P | Papa | pah-PAH | |
| Q | Quebec | keh-BECK | |
| R | Romeo | ROW-me-oh | |
| S | Sierra | see-AIR-ah | |
| T | Tango | TANG-go | |
| U | Uniform | YOU-nee-form | |
| V | Victor | VIK-tah | |
| W | Whiskey | WISS-key | |
| X | X-ray | ECKS-ray | |
| Y | Yankee | YANG-key | |
| Z | Zulu | ZOO-loo |
Numerical Pronunciation
Aviation uses specific pronunciations for digits to maximise clarity on radio. These differ from everyday speech and must be learned as standard.
| Number | Word | Pronunciation |
|---|---|---|
| 0 | Zero | ZEE-roh (not "oh") |
| 1 | One | WUN |
| 2 | Two | TOO |
| 3 | Three | TREE |
| 4 | Four | FOW-er |
| 5 | Five | FIFE |
| 6 | Six | SIX |
| 7 | Seven | SEV-en |
| 8 | Eight | AIT |
| 9 | Nine | NIN-er (always "niner", not "nine") |
Why "niner", "tree", and "fife"? In aviation, the number 9 is always pronounced "niner" to avoid confusion with the German word nein (no) on international frequencies. The number 3 is pronounced "tree" and 5 is "fife" for similar clarity reasons — reducing the chance of mishearing on degraded radio channels.
Usage in Practice
The phonetic alphabet is used whenever clarity is essential — in radio communications, when passing callsigns, waypoints, runway designators, taxiway identifiers, and any alphanumeric sequence where confusion could cause a safety issue.
E-G-L-L = Echo Golf Lima Lima
# Example clearance:
"Speedbird 123, cleared to London Heathrow via WOBUN,
squawk 4521."
# Squawk 4521 spoken digit-by-digit:
"Four Five Two One"
# NOT: "Four thousand five hundred and twenty one"
Special Cases and Usage Rules
- Always say each letter individually — never combine into syllables ("Alfa Bravo" not "AB")
- Numbers are said digit-by-digit: "Flight level Three Five Zero" for FL350
- Decimal is spoken as "decimal": "118 decimal 7" for 118.700 MHz
- Thousand is spoken for altitudes: "Ten thousand feet" (not "one-zero-thousand")
- Runway designators: "Runway Two Seven Left"
- Callsigns: "Golf Alfa Bravo Charlie Delta" for G-ABCD
Quick-Copy Card
A handy visual reference for all 26 letters. Print this page or save it for quick lookup.
Military vs. ICAO Spellings
Some military and older civilian documents may use slightly different spellings for a handful of words — most notably "Alfa" versus "Alpha". ICAO's official Doc 9835 uses the spelling "Alfa" (without the ph), as it more accurately represents the intended pronunciation across languages where "ph" may be read differently. In practice, both spellings are universally understood and accepted in operational aviation communications worldwide.
Similarly, ICAO officially spells the word for the letter J as "Juliett" (double-t) in its documentation, though single-t is common in general use. Neither variation affects meaning in radio communications.
Practice Tool
Test your knowledge of the ICAO phonetic alphabet with the interactive trainer.
Official Sources
The content on this page is developed with reference to the following authoritative publications:
New to aviation? Follow the learning path