73 means "best regards." It is the classic sign-off in amateur radio, sent at the end of a contact by Morse code, voice or digital modes. 73 in Morse code is --... ...--: the number 7 (dah dah di di dit) followed by the number 3 (di di di dah dah). This guide shows how to send and recognize it, where the number came from, how hams use it today, and a few related numbers such as 88 and 30.
Want to hear it? Type 73 into the Morse code translator and press play. The rhythm is easy to remember once you have heard it a few times.
73 in Morse code: the pattern
Numbers in Morse code are always five elements long, which makes them easy to learn as a group. The two digits in 73 are mirror images of each other:
| Digit | Morse | Sounds like |
|---|---|---|
| 7 | --... |
dah dah di di dit |
| 3 | ...-- |
di di di dah dah |
| 73 | --... ...-- |
dah dah di di dit, di di di dah dah |
The 7 is two dashes then three dots; the 3 is three dots then two dashes. Because of that symmetry, 73 has a smooth, almost musical rhythm that experienced operators recognize instantly. For the full set of digits, see the Morse code numbers chart.
How long does 73 take to send?
Morse timing is measured in units. A dot is one unit, a dash is three, the gap inside a character is one, and the gap between characters is three. Counting it out:
- 7 (
--...): 3 + 3 + 1 + 1 + 1 for the elements, plus 4 one-unit gaps = 13 units - gap between 7 and 3: 3 units
- 3 (
...--): 1 + 1 + 1 + 3 + 3 for the elements, plus 4 gaps = 13 units
That is 29 units in total. Using the standard word "PARIS" for speed, one unit lasts 1,200 ÷ WPM milliseconds, so at 20 words per minute a unit is 60 ms and 73 takes about 1.7 seconds. If those numbers are new to you, our guide to Morse code words per minute explains how speed is measured.
What does 73 mean?
In modern amateur radio, 73 is a friendly closing, roughly "best regards" or "all the best." You send it at the end of a contact, the way you might sign off a letter. It is polite, short and understood by operators everywhere, whatever language they speak.
It is not a Q-code and it is not a prosign. Q-codes such as QTH and QSL are three-letter signals that begin with Q (see our Q-codes cheat sheet). Prosigns such as SK are run-together characters with procedural meanings (see Morse code prosigns). 73 belongs to an older family: the numbered shorthand of the landline telegraph.
Where 73 came from
Long before radio, telegraph operators sent the same routine phrases over and over, so they agreed on numbers to stand for them. Sending "73" was faster than spelling out a whole courtesy.
According to amateur-radio histories that draw on the ARRL's operating manuals, the earliest known appearance of 73 is in the April 1857 edition of The National Telegraph Review and Operators' Guide. There, it meant "My love to you." (History of 73, quoting the 1969 ARRL operating manual.)
The meaning shifted over the following decades:
- 1859: Western Union's numbered "92 Code" listed 73 as "accept my compliments."
- Late 1800s: telegraph manuals gave it as "compliments" or "my compliments to you."
- Early 1900s: a 1908 edition of the Dodge telegraph manual gave the meaning used today, "best regards."
Early wireless operators came from the same telegraph culture, and they brought its habits with them. Most of the old numbers fell out of use, but 73 stayed.
How to use 73 on the air
In a CW (Morse) contact
A typical close on CW is short. Something like:
TNX FER QSO ES 73 DE [your call] SK
That reads "thanks for the contact, and best regards, from [your call], end of contact." The SK at the end is the prosign for end of work. Many operators also send a quick GL (good luck) or the other station's name before the 73. If you want to rehearse a whole exchange, the QSO simulator lets you practise a contact from start to finish.
On voice
On phone (voice) modes, say it as a number: "seventy-three." For example: "Thanks for the contact, Sam. Seventy-three from [your call]." It is not read as "seven three."
In writing
Hams also use 73 at the end of emails, forum posts and QSL cards. Writing "73, [name] [call]" at the bottom of a message is a common habit.
73 or 73s?
You will hear "73s" and "best 73s" on the air, and nobody will be confused. But the traditional view, repeated in operating guides, is that 73 already means "best regards," so adding an s is like saying "best regardses." Plain "73" is the standard form.
The same applies to 88: it already means "love and kisses," so "88s" is redundant.
Other numbers from the same code
A few of the old telegraph numbers are still around:
| Number | Morse | Meaning today | Where you'll see it |
|---|---|---|---|
| 73 | --... ...-- |
Best regards | Ham radio sign-off |
| 88 | ---.. ---.. |
Love and kisses | Ham radio, between family members or close friends |
| 30 | ...-- ----- |
The end, no more | Old press wire; "-30-" at the end of news copy |
88 is the one to be careful with. It is affectionate, so it is normally sent to a spouse, partner or close friend rather than to a stranger after a first contact. If you want the full message instead of a number, see I love you in Morse code.
Practising 73 by ear
Like any Morse character, 73 is best learned as a sound, not as dots and dashes on paper. A few simple steps:
- Listen first. Play 73 several times in the translator at a comfortable speed.
- Say the rhythm. "Dah dah di di dit, di di di dah dah." Saying it helps the pattern stick.
- Send it. Tap it on a key, a keyboard or a table. Try the Morse code trainer to check your timing.
- Hear it in context. Practise the full closing line,
TNX FER QSO 73 SK, so you recognize it when it arrives at speed.
If you are still learning the alphabet, our ham radio and Morse code guide covers the basics of an on-air contact, and the CW translator post explains how to decode common CW abbreviations.
Common mistakes when sending 73
Even a two-digit number has a few traps for new operators.
- Running the digits together. Without the three-unit gap between characters,
--...and...--blur into a single long run of ten elements that nobody can read. Leave a clear space after the 7. - Miscounting the dots. A 7 has three dots, not two. Two dashes and two dots is the letter Z (
--..), so a short 7 turns 73 into Z and a 3. - Mixing up 7 and 3. Because the two digits mirror each other, it is easy to send 37 by mistake. Think "dashes first, then dots first."
- Rushing the end. The last two dashes of the 3 often get clipped when operators speed up for the sign-off. Give each dash its full three units.
- Adding an s. As covered above, plain 73 is the standard form.
A quick fix for all of these is to record yourself sending 73 ten times and play it back through an audio decoder. If the decoder reads it cleanly every time, so will the station at the other end.
Why only a few numbers survived
The 1859 code ran from 1 to 92, and it included practical messages such as "wait a minute," "what time is it?" and "busy on another wire." Once operators could talk to each other in plain language over better equipment, most of those numbers were no longer needed. The ones that survived were social rather than technical: a courtesy (73), an affectionate goodbye (88) and an end marker (30). They lasted because they say something friendly in very little time, which is still useful on a crowded band.
73 beyond the radio
Because it is short and has a clear meaning, 73 shows up outside the shack:
- Jewelry and gifts.
--... ...--engraved on a bracelet or tag makes a quiet nod to a ham friend. Our guide to Morse code jewelry has more ideas. - Tattoos. A small 73 in Morse is a popular choice for operators. If you are planning one, check the spacing carefully; see Morse code tattoo ideas.
- Silent Key tributes. When an amateur radio operator dies, fellow hams often close a tribute with "73" alongside the term Silent Key.