Thann is a commune in the northeastern French department of Haut-Rhin, in Grand Est. It is the sous-préfecture of the arrondissement of Thann-Guebwiller and part of the canton of Cernay. Its inhabitants are known as Thannois.

Haut-Rhin is a département in the Grand Est region, France, bordering both Germany and Switzerland. It is named after the river Rhine. Its name means Upper Rhine. Haut-Rhin is the smaller and less populated of the two departments of the former administrative Alsace region, the other being the Bas-Rhin. Especially after the 1871 cession of the southern territory known since 1922 as Territoire de Belfort, although it is still rather densely populated compared to the rest of metropolitan France. It had a population of 767,083 in 2021.