Earth’s rapidly changing climate is particularly evident in the Arctic. Outside of the Arctic, the emergence of large-sample catchment databases has transformed science from an emphasis on local case-studies towards more systematic insights into drivers of watershed functioning. Here we present an integrated pan-ARctic CAtchments summary DatabasE (ARCADE) of >40,000 catchments, including small and medium-sized watersheds, draining into the Arctic Ocean. These watersheds, delineated at a high-resolution (90 m), are provided with 103 geospatial, environmental, climatic, and physiographic catchment properties. ARCADE is the first aggregated database of pan-Arctic river catchments that includes small watersheds at a high resolution. These small catchments are experiencing the greatest climatic warming while also storing large quantities of soil carbon in landscapes that are especially prone to degradation of permafrost (i.e., ice wedge polygon terrain) and associated hydrological regime shifts. The publication of this database is a necessary step toward more integrated monitoring of the pan-Arctic watershed.