521 (2016 population: 915) is a rural municipality (RM) in the Canadian province of Saskatchewan within Census Division No.

521 was originally incorporated as a rural municipality on August 1, 1977.

In the 2021 Census of Population conducted by Statistics Canada, the District of Lakeland No.

521 is governed by an elected municipal council and an appointed administrator that meets on the second Monday of every month.

[4] The reeve of the RM is Walter Plessl while its administrator is Tammy Knuttila.