Public transportation from Helsinki Vantaa Airport:

The new 18 kmRing Rail Line train connection, partially underground, opened July 10, 2015 - enabling  passengers to travel directly from the Airport to Helsinki's city center by train.  (Both Helsinki Airport & Aviapolis stations are 40 meters below ground.)  Passengers may board the train directly at the new train station under the Terminal, accessible from  its sub-level, reached via escalator or elevator.
Those catching long-distance trains (which use the Ring Rail Line) may change over at Tikkurila station which
offers connecting  commuter & long-distance trains (including to St.Peterburg & Moscow).
Ticket Purchase:  You can buy a ticket from the ticket machines on the platform (at the further end of the station, where entrance to the terminal will be opened there later.  The regional ticket costs 5 euros. valid 90 minutes from the time of purchase on all HSL transport within Helsinki, Vantaa, Espoo & Kaunianien.

Daytime & overnight buses by Matkahuolto & ExpressBus depart from the Airport Coach Terminal. 

Bus stops at T1
Bus stop 1: Finnair City Bus
Bus stop 3: to Tampere

Bus Stops at T2
Bus across from Arrivals 2A:
Bus stop 10: Finnair City Bus
Bus stop 13: to Tampere
   (b) Buses across from Arrivals 2B include Bus Stops 11-14, 21-24, 31-34 & a bit further southwest of Bus 34 are buses 35, 36:
Bus stop 3 is to Tampere
Bus stop 11: AirPort Bus, hotel shuttle buses
Bus stop 12: Bus to Remote Car Park Bus stops 13–14: Express buses, bus 540
Bus stop 21: Bus 615 to Helsinki city centre, 620N
Bus stop 23: Buses 519, 519A, 520
Bus stop 24: Bus 51

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