Wien / Vienna to Bratislava by train

Final Destination: Bratislava Hlavná Stanica (hl.st)

All trains also call at: Wien-Semmering

There are two train services between Wien Hbf and Bratislava and they both depart hourly during the day.

However, one service (this service) terminates at Bratislava hl.st. station and the other terminates at Bratislava-Petrzalka station.

So it's worth checking which station in Bratislava is closest to your final destination.
It’s likely to be Bratislava hl.st. as it’s closer to the old town and the main tourist destinations.
Bratislava-Petrzalka station is on the opposite bank of the River Danube.

You might expect quality express trains would cover the shortest distance between two European capital cities, but the regular train service is provided by Austrian commuter trains that operate over the border into Slovakia.
The newly added Railjet train between Wien and Bratislava is usually scheduled to depart from Wien Hbf at 20:42

Book early and save: No

Tickets will cost the same price if purchased at the station immediately before departure.

If you do want to book online, then on the OBB ticket booking service, look for the trains that terminate at Bratislava hl.st. and avoid those that terminate at Bratislava-Petrzalka station (unless your final destination is to the south of the city centre).