Under the German system of Naturräume, Stadtallendorf lies in the West Hesse Depression zone (westhessische Senkenzone) which is divided into basins and ridges.

[1] where Nazi Germany general and staff officers (more than 200) such as Franz Halder and Heinz Guderian[4] and scientists such as Wilhelm Schaefer were interrogated after World War II.

As of the last municipal elections held on 27 March 2011, town council seats are apportioned thus: Stadtallendorf's civic coat of arms might be described thus: In azure, dexter a bear rampant sinister Or armed gules and langued Or, sinister a lion rampant striped per fess nine times in gules and argent (the Lion of Hesse), langued gules and armed Or, both holding a six-spoked wheel argent (the Wheel of Mainz).

The town is economically successful, as large factories such as Ferrero oHG mbH (confectionery), Fritz Winter GmbH & Co. KG (engine foundry), Hoppe AG (lock manufacturing), and others have chosen to build here.

The town's transport connections are by road to the Federal Highways (Bundesstraßen) B 454 and B 62, and by rail to the railway station on the Main-Weser line.

An extension to Bundesautobahn 49 is currently being discussed, but there have been ecological questions about the wisdom of such an undertaking: the Herrenwald (masters' woods) is home to the Great Crested Newt, which is on the list of protected species.