The official list is payware: https://www.iata.org/en/publications/store/airline-coding-directory/ https://www.iata.org/en/publications/store/airline-coding-di.

The official list is payware: https://www.iata.org/en/publications/store/airline-coding-directory/ https://www.iata.org/en/publications/store/airline-coding-di... Alternatives are to scrape some other website (who presumably paid IATA for the data) or Wikipedia (https://en.wikipedia.org/wiki/Lists_of_airports_by_IATA_and_ICAO_code https://en.wikipedia.org/wiki/Lists_of_airports_by_IATA_and_...) which may or may not be more complete/accurate than OpenBSD's own crowdsourced list.