Czech Airlines a.s. is the national airline of the Czech Republic. Its head office is on the grounds of 6th district Prague, Vokovice. The airline's hub is at Václav Havel Airport Prague; however, it has other bases in the Czech city of Karlovy Vary and the Slovak cities of Bratislava and Košice. Today, it operates scheduled, charter, and cargo flights.

The airline runs a frequent flyer programme called "OK Plus" in reference to the airline's IATA designation, as well as the term of approval; OK also featured prominently in its previous livery, and is the prefix for the Czech Republic on aircraft registrations. It is a member of the SkyTeam alliance. Czech Airlines have two main shareholders, Travel Service (78.9%) and a Czech state company Prisko (20%) although Travel Service plans to acquire Prisko's stake, leaving Travel Service with a 97.74% stake in the airline.Formerly, Korean Air held a 44 percent stake, which it sold to Travel Service in October 2017.

In summer season, ČSA flies to 50 destinations in Asia and Europe. Czech Airlines carried 2.26 million passengers in 2016, which is 13% increase compared with 2015.[10] Czech Airlines Technics is responsible for aircraft maintenance and Czech Airlines Handling is responsible for passenger and aircraft handling.

ČSA is the fifth oldest still operating airline in the world, older are only Dutch KLM (1919), Colombian Avianca (1919), Australian Qantas (1920) and Soviet/Russian Aeroflot (1923). It is also the second airline to initiate successful jet airliner services (in 1957 using the Tu-104) and simultaneously the first airline in the world to fly regular jet-only routes (between Prague and Moscow)