The new Airport railway station opened September 2015, after completion of the the modernization work on the 11.9 km route from Krakow Glowny station.
The train runs every 30 minutes during the day with a reduced service in the evenings. The trip takes 18 minutes.  Some trains will continue to Wieliczka.
For more information open http://www.malopolskiekoleje.pl/index.php/pierwsza-strona

Buses 208, 292 & 902
For bus 208 open http://rozklady.mpk.krakow.pl/aktualne/0208/0208rw02.htm
For bus 252 open http://rozklady.mpk.krakow.pl/aktualne/0292/0292rw02.htm
For bus 902 open http://rozklady.mpk.krakow.pl/aktualne/0902/0902rw02.htm

NOTE:  It is important that you check current scheduling, as the above lines may still be under temporary route change. 
For time tables open http://rozklady.mpk.krakow.pl/index.php

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