Prague Airport by public transport
Prague International Airport, also variously known as Ruzyně Airport or Václav Havel Airport Prague, is located some 17 km to the north-west of Prague. Unfortunately for such a busy airport there is no metro or rail service, although a rail link is planned for the future. The cheapest and most frequent option to travel from the airport to central Prague is by bus and metro. There is also a less-frequent but direct Airport Express bus to the main railway station at slightly higher fares (normal public transport tickets not valid). A further option at even higher fares involves minibuses. Further details of all these options are shown below:
Bus and Metro
There are two bus routes from the airport that feed into different metro lines, so it's worth working out in advance which is the most convenient for your destination. In both cases you get off the bus at the last stop on the route, so there is no need to worry about missing the stop. Overall it will take about 50 minutes to reach central Prague.
Bus 119 is the most frequent service, running from the airport every 5 to 8 minutes (every 10 minutes evenings and Sunday mornings) to Nádraží Veleslavín metro station on metro line A (this is one of the stations on the new metro extension which opened in April 2015, but note it is not the last stop on the line). The bus starts from Terminal 1 and calls at Terminal 2 (flights from Schengen countries), taking 17 minutes to Nádraží Veleslavín.
Bus 100 runs from the airport (Terminal 1 and Terminal 2) to Zličín metro station, the last station on line B, taking 18 minutes. It is not as frequent as route 119 and runs every 15 minutes on Mondays to Fridays but only every 30 minutes at weekends and during the evenings, so if you have just missed one it may work out better to change your plans and catch a 119 instead.
The normal Prague tariff applies, as described on the Public Transport page. You can buy your ticket from the DPP information office in the arrivals hall or from one of the yellow ticket machines situated by the bus stops outside the terminal.
Airport Express Bus
The Airport Express or AE is a special direct bus service between the airport and the main railway station Praha hlavní, taking 46 minutes. Although operated by DPP buses, it is run on behalf of Czech Railways, so normal Prague fares do not apply. Most buses are now in the blue and white colours of Czech Railways. The single fare is 60 CZK, as opposed to 32 CZK by bus and metro. Children aged 6 to 15 pay half fare. It runs every 30 minutes in winter, increased to every 10-15 minutes in summer (detailed timings are below). Buses leave from Terminal 1 (Terminal 2 is no longer served in this direction).
TIMETABLE Airport Terminal 1 to Praha hlavní station
Winter: every 30 minutes 0530-2100.
May 1-31, Sept. 1-30: every 30 minutes 0530-2100 (every 15 minutes 0900-2000).
June 1 - August 31: every 30 minutes 0530-0830 (also 0845); every 10 minutes 0900-1430; every 15 minutes 1430-2000; also 2030, 2100.
Departures from Praha hlavní railway station to the airport are from outside the old building on the upper level - look for the ornate dome in stark contrast to the modern concourse underneath. Access to this area from the main (low level) concourse is by escalator or stairs, or there is direct access from Platform One. For timings see below. Journeys are scheduled to take 30 minutes to Terminal 1, and also call in this direction at Terminal 2 (two minutes later), but allow for delays at times of heavy traffic.
TIMETABLE Praha hlavní station to Airport Terminals 1 and 2
Winter: 0530; every 30 minutes 0630-2200.
May 1-31, Sept. 1-30: 0530; every 30 minutes 0630-2200 (every 15 minutes 0800-1900).
June 1 - August 31: 0530, 0630, 0700, 0730, 0745; every 10 minutes 0800-1330; every 15 minutes 1330-1900; every 30 minutes 1900-2200.
Prague Airport counts as a 'station' on the Czech Railways system so you can buy through rail tickets between the airport and principal stations in the Czech Republic, using the Airport Express bus between the airport and the main station. Through rail tickets can be purchased and printed online (just show it to the bus driver) but it is not possible to buy rail tickets at the airport as far as I know. If you don't already have your rail ticket you will need to pay cash to the bus driver for the bus journey, then buy your rail ticket at the main station. Buying the ticket online in advance obviously saves you having to queue for your rail ticket, and queues can be quite long. Further details (in english) are available on the Czech Railways website.
Other Bus Services
The airport is also served by bus route 191 which wends its way from the airport through the western suburbs of Prague to Andĕl metro station, terminating at the nearby Na Knížeci bus station. It runs to an irregular timetable every 20 to 30 minutes, but only every 40 minutes late evening (also early morning at weekends). If you know what you are doing or are prepared to research in advance, it can be useful for linking with trams at Petřiny or Vypich. If you have heavy bags this could save you having to lug them up and down stairs to the metro. For example, say you were staying at a hotel in the western part of Prague on one of the tram routes to Petřiny, and wanted to travel to the airport in the morning rush hour. Rather than join a crowded tram towards the city centre followed by the metro and a bus, it's actually far easier to catch a tram going out of town, get off the tram at the last stop (Petřiny), cross the road to the bus stop opposite, and catch bus 191 to the airport. You might want to check timings online first. The normal Prague tariff applies. Note that bus 191 is a fairly new route to the airport, replacing bus 179.
The DPP website has further information about travel to and from the airport.
During the night the airport is served by night bus 510 approximately every 30 minutes (every 20 minutes on Friday and Saturday nights). In the city centre it serves I.P. Pavlova before heading for the southern suburbs. Connections with other night bus routes are available at I.P. Pavlova. You can check timings online. There are no special fares for night services as they are covered by the normal tariff.
A further option is the Cedaz minibus service operated every 30 minutes 0730-1900 between the airport and V Celnici Street (outside the Czech Airlines office) in the city centre, approximately 150 metres from Náměstí Republiky and a similar distance from Masarykovo railway station. The fare is 150 CZK and the journey takes about 30 minutes. You can buy tickets from their offices located in both arrivals terminals or from the driver - no need to reserve in advance. For further details see www.cedaz.cz.