The Laaer Ostbahn begins at Wien Hauptbahnhof in Vienna and then turns north, splitting from the Eastern Railway and crossing the Donaukanal and Danube.

Continuing north, the line terminates at Laa an der Thaya, on the border with the Czech Republic.

[1] The line beyond Laa an der Thaya [de] to Hevlín and Brno was severed in 1945, as a result of the Second World War.

[2] The southern end of the Laaer Ostbahn hosts the S1 and S80 of the Vienna S-Bahn, as well as Regional-Express and Regionalzug services, all of which leave the line at Wien Erzherzog-Karl-Straße and use the Marchegger Ostbahn for Wien Aspern Nord, Marchegg, or Bratislava main.

[3] On the northern end, Regional-Express and S2 trains join the line at Gerasdorf, coming off the North railway.