There currently is one option to travel by night train from Graz to Stuttgart, taking approximately 10 hours: Namely the EN 414 operated by ÖBB.
The Austrian Federal Railways (ÖBB) operate the Nightjet and Euronight trains (the latter together with other national railway agencies). The ÖBB usually offer three types of carriages in their night trains: seats, couchettes, and sleepers. While seats are only for the bravest, couchettes and sleepers offer a more comfortable journey. Couchettes accommodate up to six people, while sleepers are private compartments for one to three people. They may include a private bathroom or shower, or sometimes just a sink.
For the next 7 dates with connections, the cheapest offer starts at 25 EUR. Check our connection pages below for all availabilities!