Phase one will see the Wettmannstätten - Wies-Eibiswald section electrified by 2025-26, which will enable to operation electric services from Graz to Wies-Eibiswald via the Koralm railway which connects to the GKB line at Wettmanstätten.

At the same time the section from Graz main station to Graz Köflacher station will be electrified to allow electric trains to reach the depot.

The remaining GKB network will then be electrified by 2028.

GKB will procure 25 to 30 new EMUs to replace the existing fleet of DMUs and double-deck push-pull coaches.

In addition, a 1.2km section of the Graz - Lieboch line will be doubled between Wetzelsdorfer Street and Grottenhof Street within the Graz city limits, which is required to enable a 30-minute-interval services.