The Erfurter Bahn is a railway company and public transit system serving the city of Erfurt, the capital of Thuringia, Germany. Erfurter Bahn is a wholly owned subsidiary of the Erfurt city council, and Süd-Thüringen-Bahn, operating between Erfurt and Meiningen, is a subsidiary of the former. Services are operated by Regio-Shuttle RS1 and Bombardier Itino trains.

Süd-Thüringen-Bahn GmbH (STB) is a public, non-state-owned railway company founded on 10 December 1999. The shareholders are Erfurter Bahn GmbH (EB) and Hessische Landesbahn GmbH (HLB), each with a 50 percent stake. The company is based at Erfurter Bahn in Erfurt, Thuringia. The operating location and operational management are located in Meiningen, Thuringia.