Airline callsign number and letter combos

Always wondered how airlines choose their callsigns so say BA flight 636 may be BAW72R or Jet 2 flight 1256 may be EXS48TX for example?

Is there a rational or some random number and letter generator? Always been curious!


Airlines choose everything for their call signs. Like American, uses AA, and the call sign sometimes relates to the plane or flight.

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There are two types of callsigns, check for the IATA and ICAO differences on the web, and you have you answer there!😄

That’s the airport code… @Neman_Rahmani

Heres the reference I think Airline codes - Wikipedia

Well that’s true but they also applies to the callsigns also, check the topic below to get a better understanding!😄

There is an ICAO and IATA for both airports and airlines.

Use this as a simple guide. I am using an example flight, Salt Lake City to San Francisco on Delta.

IATA Airports:


ICAO Airports:


IATA Airlines:


ICAO Airlines:


In America, it is more basic. But in Europe, it can be complex. For example, EasyJet 1310 can be said in IATA as U2 1310 (U2 for their code). As ICAO, it is EZS51UQ. Now this May seem random, but it is not.

According to FR24, that in order to arrive at alphanumeric call signs, certain airlines append a character to the flight number. Basically, airlines can remove a number, and replace it with a corresponding letter. So (for simplicity purposes), we can say A=1 and Z=26. Using that, we can say that United flight 9426 can be written as UALJ4Z. So Aer Lingus flight 174 becomes EIN17A (or Shamrock One Seven Alfa over the radio).


Exactly as @CaptainZac told you in the example overhead

Interesting. American airlines seem to use only numbers

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