The city belongs to the meso-region of Sul e Sudoeste de Minas and to the micro-region of Passos.

[6] The city center of Cássia is located at an elevation of 745 meters in a fertile region between the state boundary of São Paulo and the great reservoir of Furnas.

Neighboring municipalities are: Delfinópolis (N), Passos and Itaú de Minas (E), Pratápolis (S), Captetinga (SW), and Ibiraci (W).

The highest ranking municipality in Minas Gerais in 2000 was Poços de Caldas with 0.841, while the lowest was Setubinha with 0.568.

In more recent statistics (considering 5,507 municipalities) Manari in the state of Pernambuco has the lowest rating in the country—0,467—putting it in last place.