The "arrondissement" of Thann-Guebwiller is in the western part of the Haut-Rhin department. It is bordered to the north and northeast by the Colmar-Ribeauvillé "arrondissement", to the east by the Mulhouse "arrondissement", to the south by the Altkirch "arrondissement", to the southwest by the Territoire de Belfort and to the west by the Vosges department.