Public Transportation from Stockhom Arlanda Airport:   Sunfleet car pooling /shared rides is now available at the these Swedish airports:  Stockholm Arlanda, Göteborg Landvetter and Malmö Airport.  Sunfleet members may now combine car and air travel in a quick & cost-effective way.

By Train:
The railway station for the Arlanda Express can be reached from each terminal's basement level; it is served by a high-speed train, stopping at each of the Terminals (free there) and running every 15 mins, taking 20 minutes to the Stockholm Central Station - with nationwide connections.  Tickets are available at information desk or at train station's machines.
A new commuter train service available at SkyCity serves Stockholm's Central Station in 38 mins, and to Uppsala in 18 mins..
The Upptaget trains
run between Uppsala & Upplands Vasby, changing in Upplands Vasby to suburban trains to Stockholm. 

By Bus
Swebus runs a route between the Airport and Stockholm's 'Cityterminalen'  bus station with over 40 daily departures. Its ticket machines are in the terminals & at the bus stops; you can also pay on board by credit card, SMS or e-ticket. 
SL public night buses 592 & 593 run between the Airport & central Stockholm.
The Airport bus 'Flygbussarna'* stops at Terminal 2, in front of Arivals, runs every 10-30 mins. to City Center and takes about 40 mins.
SL coaches
make several stops in northern Stockholm County, Stockholm city center & Central Station.

'Bus4You' offers daily connections between the Airport and Vasteras
* Flygbussarna now offers connections between Arlanda & Bromma Airports, stopping at Sundbyberg & Kista. 

Each of the terminals is served by:
Bus line 801 (Uppsala);
Bus line 802 (Ar-Knivsta-Uppsala),
Bus line 803 (Sigtuna-Balsta-Enkoping) &
Bus line 806 (Almunge-Knutby).

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