Status: checked against official sources; automated independent review
FREQUENT FLYER GLOSSARY
What is an IATA airline code?
An IATA airline code — formally the IATA airline designator — is the two-character code that the International Air Transport Association (IATA) assigns to an airline so that the carrier can be identified in reservations, tickets and schedules. IATA describes its airline and airport code search as an official source for the codes it assigns, and the tool works in both directions: you can find the two-letter code of an airline, or identify which airline a given two-letter code belongs to. [1]
Facts checked: 18 October 2026
Key takeaways
- The code is two characters long, and those characters are not always letters: IATA's list of current member airlines shows M0 against Aero Mongolia and P5 against Aero Republica. [3]
- IATA's member list keeps the IATA Designator, the three-digit code and the ICAO code in three separate columns of the same airline record, so they are different identifiers rather than different formats of one identifier. [3]
- Where two carriers hold the same code, IATA marks it with an asterisk and calls it a "Controlled Duplicate", used for different types of non-overlapping service. [1]
- One search covers both kinds of code: two-letter airline codes and three-letter airport codes. [1]
What does an IATA airline code look like?
IATA's search tool labels the airline field as the "2-letter code" of an airline, and the airport field as the three-letter code of an airport; an airline query returns two results, while an airport query can return up to five. [1]
On IATA's own member list, though, the field is two characters rather than strictly two letters. That list records each member airline's IATA Designator, three digit code, ICAO code and country or territory, and it contains designators pairing a letter with a digit — M0 for Aero Mongolia, P5 for Aero Republica — alongside letter-only ones such as EI for Aer Lingus and SU for Aeroflot. [3]
| Airline | IATA designator | 3 digit code | ICAO code | Country or territory |
|---|---|---|---|---|
| Aegean Airlines | A3 | 390 | AEE | Greece |
| Aer Lingus | EI | 053 | EIN | Ireland |
| Aero Mongolia | M0 | 970 | MNG | Mongolia |
| Aeroflot | SU | 555 | AFL | Russia |
| Aeroitalia | XZ | 419 | AEZ | Italy |
| Aeromexico | AM | 139 | AMX | Mexico |
How do you look up an airline's IATA code?
The authoritative lookup is the IATA airline and airport code search, which the association presents as an official source for the codes it assigns. For airlines, it answers both directions: type a code to see which carrier holds it, or search by carrier to see the code. [1]
For larger reference needs, IATA points users to its Airline, Airport and Location Coding Databases, which hold airline, airport and intermodal location codes. [1] The code search is grouped on IATA's site with references including the Ticketing Handbook, the Reservations Handbook, the City Code Directory and the Multilateral & Bilateral Interline Traffic Agreements. [1]
Because the same tool also handles airport codes, check which kind of code you are holding before acting on it — a two-character airline designator and a three-letter airport code are separate fields with separate lengths. [1]
How is the designator different from an airline's three-digit code?
An airline's entry in IATA's member list can carry more than one identifier, and each sits in its own column: the IATA Designator, the "3 digit code" and the ICAO code. Aegean Airlines appears as A3, 390 and AEE; Aer Lingus as EI, 053 and EIN; Aeromexico as AM, 139 and AMX. [3]
The two-character designator is the field IATA's public code search returns. The numeric code (see airline numeric code) and the ICAO code are recorded alongside it, so a record can show three different identifiers for the same carrier, each in its own field. [3]
Designators are also written differently from airport codes across the same reference set: airline codes are two characters, airport codes three letters. [1]
Exceptions and limits
- Shared codes. Codes marked with an asterisk in IATA's search are "Controlled Duplicate" cases, where two carriers have the same code but operate different types of non-overlapping services. [1]
- Two characters, not always two letters. A digit can appear in a designator, as M0 for Aero Mongolia and P5 for Aero Republica show. [3]
- Result limits. The public airline search returns two results per query and the airport search up to five; IATA directs users who need more to its coding databases. [1]
- The list is live, not fixed. The member list reported 380 airline members when checked on 18 October 2026, and 19 airlines had joined the IATA membership community in 2026. [3]
- What the term does not cover. An airline designator is not an airport code, and it is not the three-digit code or the ICAO code printed beside it in the same record. [1] [3]
Frequently asked questions
Can an airline's IATA code contain a number?
Yes. IATA's member list includes M0 for Aero Mongolia and P5 for Aero Republica among its designators. [3]
Where can I look up an IATA airline code?
In IATA's airline and airport code search, which the association describes as an official source for codes assigned by IATA. [1]
Why do two airlines sometimes share the same code?
IATA's search marks those with an asterisk and defines them as "Controlled Duplicate", where two carriers hold the same code but operate different types of non-overlapping services. [1]
Is the two-character code the same as the three-digit code on an airline record?
No. IATA's member list keeps the IATA Designator and the "3 digit code" in separate columns, with a separate ICAO code as well. [3]
What is the difference between an IATA designator and an ICAO code?
They are separate fields of the same airline record, and they do not look alike: Aeroitalia's entry shows XZ as its IATA Designator and AEZ as its ICAO code. [3]
Sources
Sources checked on 18 October 2026. No frequent flyer programme is covered here: this term describes the airline designator itself rather than any programme's earning, redemption or status rules.
- IATA airline and airport code search, checked 18 October 2026
- IATA current airline members list, checked 18 October 2026