Sulfate is one of the dominant ions in northern rivers and concentrations have been increasing in recent decades due to climate change impacts on hydrological processes and geological weathering rates in cold regions. As part of various water quality research and monitoring activities in the Yukon, water samples were collected from surface waters (rivers, creeks, lakes) and groundwater (wells, drive-point piezometers, springs) in 2017 and 2018. In addition to analyzing these samples for major ion concentrations, including sulfate, stable isotope analysis of sulfate (δ18O, δ34S) and water (δ18O, δ2H) was done to investigate the sources and processes contributing sulfate to these natural waters. Information on the analytical methods used and interpretation of the dataset can be found in the following peer-reviewed publication: Chemical Geology 631: 121510. (2023) https://doi.org/10.1016/j.chemgeo.2023.121510