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D in the NATO Phonetic Alphabet
In the NATO (ICAO) phonetic alphabet, the letter D is spoken as "Delta". Say "Delta" whenever you need to spell D clearly over the phone, on a radio or across a language barrier — on a bad line "Delta" cannot be confused with similar-sounding letters the way a bare "D" can (think of the classic B/P/T/D/V mix-up). It uses the official ICAO spelling, the same one used by pilots, ships, the military and call centres. See the full A–Z chart on the tool for every other letter, and the ICAO digit words (3 = Tree, 4 = Fower, 5 = Fife, 9 = Niner). Type any name or code to convert it entirely in your browser. Free, no login.
D = Delta
- Spoken: say "Delta" for the letter D — e.g. "D as in Delta"
Frequently asked questions
How do you say the letter D in the NATO phonetic alphabet?
The letter D is spoken as "Delta" in the NATO/ICAO phonetic alphabet. So to spell out a D clearly you say "Delta" — for example, "D as in Delta." This is the official ICAO spelling used in aviation, shipping, the military and customer service.
Why use "Delta" instead of just saying "D"?
Single spoken letters are easy to mishear over a phone or radio — D can blur into other letters, especially through static or a strong accent. Replacing it with the long, distinct word "Delta" makes it unmistakable, which is exactly why the phonetic alphabet is the international standard for reading out names, codes and reference numbers.