Reference
NATO military signals identify each fixed UTC offset with a single letter and a NATO phonetic name. Zulu is UTC, the rest run A through M for positive offsets (skipping J) and N through Y for negative. J ("Juliet") means the observer's local time.
| Letter | Phonetic | UTC offset | Example zones |
|---|---|---|---|
| Z | Zulu | UTC |
Zulu time is the most-used letter in aviation, the military, and Unix system clocks. Every weather report (METAR/TAF) carries a Z suffix. |
| A | Alpha | UTC+01:00 |
|
| B | Bravo | UTC+02:00 |
|
| C | Charlie | UTC+03:00 |
|
| D | Delta | UTC+04:00 |
|
| E | Echo | UTC+05:00 |
|
| F | Foxtrot | UTC+06:00 |
|
| G | Golf | UTC+07:00 |
|
| H | Hotel | UTC+08:00 |
|
| I | India | UTC+09:00 |
The letter I and the phonetic India are unrelated to the Indian Standard Time zone — India observes UTC+05:30, which has no single military letter. |
| K | Kilo | UTC+10:00 |
|
| L | Lima | UTC+11:00 |
|
| M | Mike | UTC+12:00 |
M is the eastmost fixed-offset letter. Time zones east of that — Kiribati, Samoa, Tonga at +13 — fall off the alphabet and have no standard letter. |
| N | November | UTC-01:00 |
|
| O | Oscar | UTC-02:00 |
|
| P | Papa | UTC-03:00 |
|
| Q | Quebec | UTC-04:00 |
|
| R | Romeo | UTC-05:00 |
|
| S | Sierra | UTC-06:00 |
|
| T | Tango | UTC-07:00 |
|
| U | Uniform | UTC-08:00 |
|
| V | Victor | UTC-09:00 |
|
| W | Whiskey | UTC-10:00 |
|
| X | X-ray | UTC-11:00 |
|
| Y | Yankee | UTC-12:00 |
Y is the westmost military letter. Almost no inhabited zone uses UTC-12 — it survives on charts mostly to mark the antimeridian. |
| J | Juliet | Local | No fixed offset. Juliet is not a fixed offset. It tells the reader "the observer's local time, whatever that is." Used in field signals where the writer wants to leave the reader to apply their own zone — and avoided in international communications because it is ambiguous. |
Military time zone letters live in three places. Aviation METAR and TAF reports end their date-time group with a Z — for example, `301200Z` means the 30th of the month at 12:00 UTC. NATO message signals use the same convention so a one-letter suffix tells the reader exactly which clock the timestamp is anchored to. And ham radio operators still log contacts in UTC and call it Zulu out of habit.
Military letters describe a fixed offset. Many IANA zones span two letters across the year. London sits at Z in winter (GMT) and A in summer (BST). New York sits at R in winter (EST) and Q in summer (EDT). When someone says "we'll meet at 14:00 R" in May, they usually mean 14:00 EDT — but strictly Romeo time is UTC-5, so the meeting is at 15:00 EDT. If clarity matters, name the IANA zone, not the letter.
To convert a wall-clock time between a military letter and a city, try the time zone converter with the matching IANA zone. For a list of every IANA zone with its current offset, see UTC offset globe.
J is reserved for "Juliet", which is not a number at all — it means "the observer's local time." The NATO phonetic alphabet uses J for Juliet to keep voice signals unambiguous, and the military time letter system inherits the same letter. So instead of A, B, ..., I, J, K for +1 through +11, the offsets jump from I (+9) straight to K (+10).