138 (2016 population: 541) is a rural municipality (RM) in the Canadian province of Saskatchewan within Census Division No.

138 incorporated as a rural municipality on December 13, 1909.

In the 2021 Census of Population conducted by Statistics Canada, the RM of Webb No.

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

[3] The reeve of the RM is Dennis Fiddler while its administrator is Raylene Packet.