Tannhausen is located approximately 20 km (12 mi) east of Ellwangen at the edge of the Nördlinger Ries in Swabian Württemberg close to the border of the Franconian part of Bavaria, where the administrative region of Swabian Bavaria meets Central Franconia.

The boundaries of the municipality are located in the north onto Stödtlen, in the east onto the bavarian municipalities Wilburgstetten (rural district of Ansbach, central Franconia), and Fremdingen (rural district of Donau-Ries, Swabia), in the south onto Unterschneidheim and in the far west onto the city area of Ellwangen.

Next to the main village of Tannhausen, six more communities belong to the municipality, Riepach, Bleichroden, Sederndorf, Hagenbucherhof, Bergheim, and Ellrichsbronn.

During German mediatisation in 1806, Tannhausen belonged to the State of Bavaria; however, it became later a part of the Duchy of Württemberg on January 12, 1810.

Tannhausen has one retirement home, offering living accommodations and geriatric care for 130 elderly people.