Division No. 1 is one of eighteen census divisions in the province of Saskatchewan, Canada, as defined by Statistics Canada. It is located in the southeast corner of the province, bordering Manitoba and North Dakota. The most populous community in this division is Estevan.
In the 2021 Census of Population conducted by Statistics Canada, Division No. 1 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.
The following census subdivisions (municipalities or municipal equivalents) are located within Saskatchewan's Division No. 1.