I-129, U-236, and U-238 data collected during the Fram Strait expeditions in 2020 and 2021 on the RV Kronprins Haakon and coordinated by the Norwegian Polar Institute. The dataset includes metadata, hydrographic data, and a water mass definition. This dataset compiles newly generated I-129, U-236, and U-238 data with previously published I-129, U-236, and U-238 data. U-236 and U-238 data in columns starting with "ETH" are newly generated from ETH Zurich while the remaining U-236 and U-238 data are from Lin et al. (2023). I-129 data in 2021 from stations 355, 356, 365, 366, and 368 are from Pérez-Tribouillier et al. (2025). The previously published data are reproduced here for convenience and remain subject to the original license. Hydrographic data are from Dodd et al. (2022a) and Dodd et al. (2022b).