Understanding permafrost processes and changes requires long-term observational datasets. This dataset is a continuation of the dataset available from the Bayelva Site at Ny-Ålesund, Svalbard, where meteorology, energy balance components and subsurface observations have been made for the last 20 years. The data provide observations of temporally variable parameters that mitigate energy fluxes between permafrost and the atmosphere, such as active layer and permafrost temperature, soil volumetric water content and soil bulk electrical conductivity. They are suitable for use in integrating, calibrating and testing permafrost as a component in Earth System Models. The resulting quality-controlled dataset is unique in the Arctic and serves as a baseline for future studies.