The Rural Municipality of Enniskillen No. 3 (2016 population: ) is a rural municipality (RM) in the Canadian province of Saskatchewan within Census Division No. 1 and Division No. 1. Located in the southeast portion of the province, it is adjacent to the United States border, neighbouring Burke County and Renville County both in North Dakota.
The RM of Enniskillen No. 3 incorporated as a rural municipality on December 13, 1909. Sam McKnight came to the area from Durham County, Ontario, and served as chairman of the organizing committee for the RM. He seemed to have had his heart set on a northern Irish name, since his committee proposed Enniskillen, Derry, Antrim, Boyne, Alma, Fermanagh and Waterloo. The government selected the first name on the list which honours Enniskillen (inis Ceithleann, "Ceithle's island"), the country town of Fermanagh, Northern Ireland.
The following urban municipalities are surrounded by the RM.
The following unincorporated communities are within the RM.
In the 2021 Census of Population conducted by Statistics Canada, the RM of Enniskillen No. 3 had a population of living in of its total private dwellings, a change of from its 2016 population of . With a land area of , it had a population density of in 2021.
In the 2016 Census of Population, the RM of Enniskillen No. 3 recorded a population of living in of its total private dwellings, a change from its 2011 population of . With a land area of , it had a population density of in 2016.
The RM of Enniskillen No. 3 is governed by an elected municipal council and an appointed administrator that meets on the second Tuesday of every month. The reeve of the RM is Trevor Walls while its administrator is Pamela Bartlett. The RM's office is located in Oxbow.