The relationship between δ¹⁸O and salinity has been widely studied because it can provide crucial information on the partitioning of isotopes through the hydrological cycle. Current understanding of δ¹⁸O-S characteristics has been used to constrain water cycle models, isotope-enabled atmospheric and ocean models as well as to monitor evaporation (E) and precipitation (P) changes in major ocean basins. However, in the polar regions, where large spatial and temporal variabilities in δ¹⁸O and salinity are expected due to the highly seasonal sea ice melting/formation, river runoff, E-P intensification and rapidly changing summer ice minimum, uncertainties still surround the δ¹⁸O-Salinity relationship. To observe the inputs of freshwater in a poorly-understood, but vastly changing region in the Arctic, we collected matching δ¹⁸O-Salinity data from discrete samples from the surface (bucket sampling) and from profiles (Conductivity, Temperature, Depth (CTD) casts) in the Canadian Arctic Archipelago (CAA) during the Northwest Passage expedition aboard the RV Oden last 17 July – 04 August 2019. Matching δ¹⁸O-Salinity measurements were also obtained from ice core samples as well as from a precipitation event during the cruise. Here, we present more than 200 new and paired δ¹⁸O-Salinity measurements to help represent water mass end-members for freshwater budgeting as well as understanding the changes in the CAA's hydrologic cycle.