As far as I know, airport name abbreviations are a 3 letter name. For example:

  • MEL for Melbourne/Australia airport
  • LAX for Los Angeles/USA airport
  • YYZ for Toronto/Canada airport

And that means all the options we have for naming are 26 * 26 * 26 = 17,576

Sometimes these match the IATA code, but not always. IATA codes are also 3-letter codes, but are not assigned to every airport as shown in this answer. But what about all of the other airports in the world? Will the world ever run out of "regular" airport codes?

A simple Google search about the number of the airports worldwide shows there are 17,678 airports. So are they going to extend airport codes to 4 letters or use numbers 0,1,2,...9?

Even by starting to use numbers they may reach a point where they run out of options. What is the approach to fix that ?

  • $\begingroup$ There are a lot of airports that use numeric codes, for example a popular airport near my home airport is 92C - Carter. $\endgroup$
    – Ron Beyer
    Nov 27, 2018 at 22:57
  • $\begingroup$ are you interested in IATA airport codes or ICAO airport codes? $\endgroup$ Nov 27, 2018 at 23:01
  • $\begingroup$ @selectstriker2 not sure what you call these codes MEL, LAX, YYZ $\endgroup$
    – asmgx
    Nov 27, 2018 at 23:15
  • $\begingroup$ To understand the difference between ICAO and IATA codes you can refer to this Wikipedia article. $\endgroup$
    – Gerry
    Nov 27, 2018 at 23:28
  • 1
    $\begingroup$ They are not IATA airport identifiers, but IATA location identifiers. See this answer about railway stations having IATA identifiers too. So the problem is larger :-) Here is the list of these stations. $\endgroup$
    – mins
    Nov 28, 2018 at 9:13

4 Answers 4


There are multiple airport code systems. The one you seem to be asking about is the 3-letter IATA code, which is mostly assigned to airports with scheduled commercial service--and even some railway stations; they're nowhere near running out.

4-letter ICAO codes are assigned to far more airports, and we're nowhere near running out of those globally either, though since countries are allocated 1- or 2-letter prefixes, it's rather uneven.

Some airports have only a three- or four-letter national code; this is particularly common for heliports and private fields, and one or more of the letters is often a number so they aren't confused with IATA or ICAO codes.


Only major airports get all Letters. Many of the smaller airports also incorporate numbers.

Here are some examples:

Osage City: 53K
Cle Elum: S93
De Vere: 2W1

And many, many, many more...
Once you add in letters and numbers, you'll find plenty of combinations.

  • 1
    $\begingroup$ Which, assuming 0 is not included, then becomes (26+9)*35*35 = 44100 $\endgroup$ Nov 28, 2018 at 8:16
  • $\begingroup$ 0 is used, frequently for sea-plane areas, such as 0W0 (Seattle) $\endgroup$
    – abelenky
    Nov 28, 2018 at 13:14

These are called Airport Identification Codes. The same ID code might exist in different countries, so it's not really possible to limit your 17,576 total combinations to all airports in the world. Additionally, some countries will use a combination of letters and numbers.

There are three main conventions for determining an Airport ID code:

  1. Each country has their own national authority, which assigns IDs to airports in that country
  2. ICAO - The ICAO organization has a process for each country to assign an ICAO ID to airports within that country.
  3. IATA - The IATA organization has a process for each country to assign an IATA ID to airprots within that country.

National Authority: Within each country, the national aviation authority assigns Airport IDs to all airports within its jurisdiction. For example, in the USA, the FAA assigns either 3- or 4-letter codes to its airports. There is more information on FAA-specific codes at this ASE page. The busier airports in the USA will get a 3-letter ID. These IDs will usually match the IATA code. And, within the 48-contiguous states, the 3-letter ID will be prefaced with the ICAO-designated letter "K".

International Civil Aviation Organization (ICAO).
This body assigns a prefix designator letter to geographical regions and (if necessary) a second letter to individual countries within that region. Some examples: Northern European airports all start with E, and then the UK starts with G and Germany starts with D. From there, the national authority selects the final two letters. Thus, London Heathrow's ICAO Code is: EGLL.

International Air Transport Association (IATA) IATA is not driven by the local authority, but rather by the Association itself, in cooperation with the member airlines. IATA assigns a 3-letter code to airports which receive service by IATA-member airlines.

And to get even more complicated, the same airport might have three different ID Codes, one of each.

Related reading:

Can two airports have a different ICAO code but share the same IATA code?

When do we use IATA codes and when do we use ICAO codes?


as far as i know airport names abbreviation is a 3 letters name

There are multiple lists of airports that use abbreviations and none of them are completely comprehensive.

The major lists you will see for airports around the world will be IATA and ICAO. The FAA has a separate list that is only for US airports. The three-letter abbreviations you show are from the IATA list.

Many smaller airports do not get an IATA designation. Checking a recent version of the data shows only a little over 9000 entries. So unless the allocation rate is high (which seems unlikely), there's no immediate fear of running out.

See also: Can two airports have a different ICAO code but share the same IATA code? and Where can I find a free list of ICAO and IATA airport identifiers?


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