Vienna International Airport is at Schwechat, eighteen kilometres south-east of the centre. Unlike Budapest or Prague, it has a proper rail connection — in fact three of them, from the same station beneath the terminal, and the differences between them catch people out.
The three trains
S7 (S-Bahn). The local stopping train to Wien Mitte, about 25 minutes. It is by far the cheapest, and if you already hold a Vienna time pass you only need to buy the supplement for the section outside the city zone. Runs every half hour.
Railjet / ÖBB intercity. Runs to Wien Hauptbahnhof in about 15 minutes and on to Wien Meidling. Costs a little more than the S7, and is the best option if the Hauptbahnhof suits you or you are connecting to another train.
City Airport Train (CAT). A dedicated non-stop service to Wien Mitte in 16 minutes. It costs roughly four to five times the S7 fare to save about nine minutes on a train that runs half as often. Its advantage is city check-in for some airlines at Wien Mitte. For most people it is not worth it, and the marketing at the airport is designed to make you think it is the only option. It is not — walk past the CAT desk to the ÖBB machines.
All three leave from the same underground station. Read the platform display rather than following signage colours.
The bus
Vienna AirportLines coaches run to Morzinplatz/Schwedenplatz, Westbahnhof and Kagran, taking 20 to 40 minutes depending on route and traffic. Priced between the S7 and the CAT. Useful if your accommodation is near one of the stops, since it avoids a change.
Taxis and ride-hailing
A metered taxi to the centre costs several times any train option and takes 25 to 40 minutes. Fixed-price airport transfer firms operate from a desk in arrivals. Uber and Bolt both work in Vienna and are generally cheaper than a taxi.
Which to choose
If you are heading for the centre with normal luggage, take the S7, or the Railjet if the Hauptbahnhof is convenient. Take the CAT only if you want the city check-in.
Times
Allow two hours from the centre for a scheduled departure. Vienna’s security queues are usually efficient but the terminal is large and the walk to some gates is long.
Arriving late
The last S7 runs around midnight and the first is before five. Outside those hours the AirportLines bus covers part of the gap, and after that it is a taxi.
Bratislava’s airport
Some low-cost flights sold as “Vienna” land at Bratislava, which is in another country, 55 kilometres away. There are direct buses from Bratislava airport to Vienna taking about ninety minutes. It is perfectly workable, but check which airport your ticket actually names before you book accommodation around an arrival time.
Money
Austria uses the euro. There are ATMs in arrivals — use a bank machine rather than a standalone one, and decline any offer to charge you in your home currency.
Reading the departure board
All three trains use the same underground platforms, and the boards list them by destination rather than by service type. Wien Mitte could be the S7 or the CAT; Wien Hauptbahnhof is the Railjet. The CAT has its own green branding and its own ticket gates at the platform, which is the clearest way to tell them apart.
Buy from the red ÖBB machines, not the green CAT desk, unless you specifically want the CAT.
Terminals
Terminals 1, 1A and 3 are joined and walkable; there is no separate terminal building to shuttle between. The train station is beneath the connecting hall and signed as Bahnhof / Railway Station throughout.
City check-in
The CAT’s genuine advantage is that some airlines allow you to drop your bags and get a boarding pass at Wien Mitte, up to 24 hours before departure, and then travel into the airport unencumbered. If you have a late flight and want a final day in the city without a suitcase, that is worth the fare. Otherwise it is not.
A note on the “Vienna” low-cost flights
Check the airport code on your ticket. VIE is Vienna. BTS is Bratislava, in Slovakia, and some carriers market it as serving Vienna. It works — there are direct buses — but it adds about ninety minutes each way and it is not what most people think they have booked.
Left luggage and long layovers
The airport has staffed left luggage and lockers, and Wien Mitte and the Hauptbahnhof both have lockers. With five hours or more between flights, the S7 into Wien Mitte and a walk to Stephansplatz is entirely feasible — the centre is twenty-five minutes away, which is unusual among European capitals and makes even a short layover worth leaving the terminal for.
Allow ninety minutes to get back and through security, and rather more in the early morning peak.