Big Arm No. 251 is a rural municipality in the Canadian province of Saskatchewan, located in the southern part of the province near Last Mountain Lake northwest of Regina in SARM Division No. 5 and Census Division 11.
according to the 2001 census:
Population - 250 people
Population percentage change- -16.4
Total Private Dwellings- 126
Population density per square kilometre- 0.4
Land area (square km)- 699.41
Coordinates: 51°15′38″N 105°15′38″W / 51.26056°N 105.26056°W