In Austria ÖBB operates the vast majority of trains. Four other operators: Regiojet, Westbahn, Gysev and Microtra accept Interrail in their trains as well. Other operators don’t, for example some local railways in the Alps.
Railway operators in Austria
ÖBB
ÖBB operates intercity as well as regional trains in Austria, on domestic routes within Austria you can get on their trains without needing any reservations in 2nd or 1st class, however Business class on Railjet trains does require reservations, as well as an additional fee even for 1st class pass holders.
The Innsbruck – Salzburg Railjet route runs through Germany, but does not have any stops in Germany – it counts as a domestic train, therefore if you’re a global pass holder with residence in Germany, you can use it without using inbound/outbound days, and if you have a one country pass for Austria, you can use it as well. The one country pass for Austria is also valid on ÖBB trains in Liechtenstein, which counts as a part of Austria for Interrail purposes.
You can use ÖBB S-Bahn services to get around Vienna and other cities that have S-Bahn networks, but your Interrail pass is not valid on the U-Bahn, trams, buses, Wiener Lokalbahn or the City Airport Train (CAT). It is valid on ÖBB and Regiojet trains to the Vienna airport. Besides trains, your Interrail pass is also valid on ÖBB IC Bus routes (Klagenfurt – Graz and Klagenfurt – Venice), but not on ÖBB Postbus routes!
ÖBB operates a large network of sleeper trains all over Europe, called Nightjet. Reservations are required for these trains on international routes. If you get a seat of a Nightjet within Austria, reservation is optional. For couchettes or beds reservations are always mandatory. It’s a good idea to book these early, they can get sold out months in advance.
Besides ÖBB, four other operators accept Interrail in Austria:
Regiojet
Regiojet trains on the Prague – Vienna – Budapest route require reservations, the price varies by class but it’s cheap (up to 3€). With a 2nd class pass you can reserve seats in the 3 lower classes (Low cost, Standard, Relax) while the highest Business class is restricted to 1st class pass holders. You can buy reservations at https://regiojet.cz/, or at a station at a RegioJet ticket office. For more details check the article on Czechia.
Westbahn
Westbahn trains on the Munich/Innsbruck – Salzburg – Linz – Vienna route also accept Interrail, but beware that both 1st and 2nd class pass holders can use their standard class, while the “Westbahn plus” class is available to 1st class pass holders, but only if you pay a 9.90€ upgrade (you can pay that to the conductor in the train).
Raaberbahn/Gysev
Raaberbahn/Gysev regional trains between Austria and Hungary accept Interrail on these routes: Ebenfurt to Sopron and Neusiedl am See to Pamhagen (Gr).
Micotra
They run regional trains from Villach to Tarvisio (Italy).
Reservations
Reservations are not required for the vast majority of trains – in particular all regional trains of any operator, all domestic ÖBB intercity trains, all Westbahn intercity trains. They are only required on some international routes.
Reservations for ÖBB trains (as well as trains in some neighboring countries like Germany or Italy) can be easily made on the ÖBB website or app by selecting the single tickets option, and adding the Interrail pass as a discount card. Most will be delivered by email (or just loaded in the ÖBB app), but some more exotic ones require pickup in Austria.
How to book reservation online with ÖBB, instructions with pictures on Eurail community: https://community.eurail.com/train-connections-reservations-47/how-to-get-reservations-105?postid=178#post178
Short instructions:
- Go to https://shop.oebbtickets.at/en/ticket
- Enter the trip you’re wishing to take, select time and date
- Click ‘change’ on the ‘who is going?’
- Click ‘Add discount’
- Choose ‘Interrail / Eurail – Globalpass’
- Click ‘next’
- Click ‘Find services’
- Choose ‘One-way tickets’ [not “Seat only”!]
- Select the train of your choice
- Select the ticket of your choice. Remember to select the right class – ÖBB doesn’t know if you have first or second class ticket.
- Add the reservation to the basket, fill in your details and pay.
Reservations are mandatory for:
- ÖBB IC Bus
- All Regiojet trains
- All Nightjet and EuroNight trains, except for seats on some routes (couchettes or beds always come with mandatory reservations)
- EC and Railjet trains to Italy: while seat reservations are not required, a 10€ supplement (additional fee) is. You can buy it for example from the ÖBB website or app, or at ticket offices, or pay it to the conductor in the train.
- Railjets to Switzerland
- Railjets to Hungary
Railjet, ICE and EC trains to other countries (Germany, Czechia, Slovakia, Slovenia) do not require reservations.