In the 2021 Census of Population conducted by Statistics Canada, Buchanan had a population of 237 living in 121 of its 141 total private dwellings, a change of 8.7% from its 2016 population of 218. With a land area of 1.13 km2 (0.44 sq mi), it had a population density of 209.7/km2 (543.2/sq mi) in 2021.[8]
In the 2016 Census of Population, the Village of Buchanan recorded a population of 218 living in 106 of its 118 total private dwellings, a -3.2% change from its 2011 population of 225. With a land area of 1.29 km2 (0.50 sq mi), it had a population density of 169.0/km2 (437.7/sq mi) in 2016.[9]