Snow height was measured by the Snow Depth Buoy 2018S85, an autonomous platform, drifting on Arctic sea ice, deployed with the icebreaker ODEN during the Arctic Ocean 2018 campaign (AO18). The resulting time series describes the evolution of snow depth as a function of place and time between 17 September 2018 and 13 December 2018 in sample intervals of 1 hour. The Snow Depth Buoy consists of four independent sonar measurements representing the area (approx. 10 m**2) around the buoy. The buoy was installed on multi year ice. In addition to snow depth, geographic position (GPS), barometric pressure, air temperature, and an internal ice temperature were measured. Negative values of snow height occur if surface ablation continues into the sea ice. Thus, these measurements describe the position of the sea ice surface relative to the original snow-ice interface. Differences between single sensors indicate small-scale variability of the snow pack around the buoy. The data set has been processed, including the removal of obvious inconsistencies (missing values). Records without any snow depth may still be used for sea ice drift analyses.