Montillières-sur-Orne (, literally ''Montillières on Orne'') is a commune in the Calvados
department
Department may refer to:
* Departmentalization, division of a larger organization into parts with specific responsibility
Government and military
*Department (administrative division), a geographical and administrative division within a country, ...
in northwestern France. The municipality was established on 1 January 2019 by merger of the former communes of Trois-Monts and Goupillières.
The commune is part of the area known as Suisse Normande.