Saint-Hilaire-du-Harcouët (French pronunciation: [sɛ̃.t‿ilɛʁ dy aʁkwɛ]) is a commune in the Manche department in Normandy in north-western France.

[4] It is approximately 50 miles (80 km) east of St. Malo and a similar distance northeast of Rennes.

A medieval tower in the town centre, the only remainder of the old church, contains frescos by painter Marthe Flandrin.

The average annual rainfall is 947.2 mm (37.29 in) with December as the wettest month.

The population data given in the table below refer to the commune in its geography as of January 2020.