The arrondissement of Mamers is an arrondissement of France in the Sarthe department in the Pays de la Loire region.

[2] Its population is 149,694 (2021), and its area is 2,904.9 km2 (1,121.6 sq mi).

[4] In February 2006 it absorbed the six cantons of Bouloire, Conlie, Montfort-le-Gesnois, Saint-Calais, Sillé-le-Guillaume and Vibraye from the arrondissement of Le Mans.

[6] As a result of the reorganisation of the cantons of France which came into effect in 2015, the borders of the cantons are no longer related to the borders of the arrondissements.

The cantons of the arrondissement of Mamers were, as of January 2015:[7]