Since the journey between Bregenz and Vienna is relatively short, you can consider carpooling or bus as alternative ways of transport with cheapest prices and similar duration.
When it comes to relatively long journeys like between Bregenz and Vienna, you can can consider taking a high-speed train or a plane to cut your journey's duration.
Which stations serve the rail line Bregenz - Vienna?
You can take the train to Vienna at Bregenz Bahnhof, which arrives at Wien Hauptbahnhof or Wien Hbf (Bahnsteige 1-2).
How long will it take you from Bregenz to Vienna by train and when do the trains leave?
On average, it takes 7 hours and 5 minutes to get to Vienna by train, but you will need 6 hours and 42 minutes with the fastest trains. The first one is available at 05:01, whereas the last one leaves Bregenz at 06:01.