Here you can find a manual how to reserve Nightjets via oebb.at (Even if you just wanna reserve you have to use the ticket option and not the seat only option )

 

Here you can check the reservation fee´s you can expect note the train is very popular and doesn´t operate daily sometimes it´s better to take first a IC to Amsterdam and catch the Nightjet from Amsterdam as the Route from Amsterdam is operated daily and you can take from there even a coaches to Innsbruck :)

Thanks for your response, but unfortunately it doesn't answer my question.

Is there a fixed discount / fixed price to travel with the nightjet if you have an interrail global pass ?

This for Brussels - Vienna.

I see a lot of prices of 229.90 euros, for a single deluxe sleeping cabin.

Via the reservation service I arrive at a price of 164 euros + 2 euros booking costs.

@seewulf

In the meantime I managed to find the price of 164 euros for this connection.

Thank you!

164 euro seems to be normal price for deluxe sleeper:

Standard interrail reservation price is 14 euro + 150 euro for the deluxe sleeper.

164 euro seems to be normal price for deluxe sleeper:

Standard interrail reservation price is 14 euro + 150 euro for the deluxe sleeper.

Now I finally managed to get the price of 164 euros.
I probably did something small that prevented me from getting this award.

I think it's a very good price, so I definitely want to try it someday.
Too bad I don't get any benefit with my 1st class interrail global pass, or is there still a discount with a 1st class global pass?

@seewulf 

@MartinM 

Is it true that you can only travel by Nightjet from Brussels to Vienna, and not to Innsbruck?

Yes, there is no nightjet from Innsbruck to Brussels anymore (shortage of carriages, too long train length?).

No, you don’t get any discount with a 1st class global pass.

And if you depart from Amsterdam or Cologne, in the direction of Vienna, you pay 20 euros less.

It is also indicated that there is a surcharge from Brussels. Why a surcharge from Brussels!

https://www.nightjet.com/en/buchung/tarifinformationen/interrail-eurail-paesse

Well, only two ideas:

• Brussels is the EU capital → many EU employees who can afford also +20 euro easily
• higher TAC (track access charge) in Belgium (but didn’t check that)

I notice that the price from Aachen also remains unchanged, namely 164 euros for the same train that departs from Brussels.

I don't know if there are viable connections from Brussels with ICE or IC, to get on the Nightjet from Germany, which makes the price less than when departing from Brussels.

Track access in Belgium for passenger trains is indeed quite expensive. Additionally, ÖBB uses NMBS/SNCB to transport this train in Belgium and they aren't cheap either. That was one of the reasons the former night trains to Warsaw and Vienna and also Paris - Brussels - Berlin/Hamburg disappeared from Belgium about 15 years ago.