Ecosystems that experience fire activity within their natural range of variability tend to be resilient and persist in the long run, while departures from that natural range are associated with ecosystem loss and type conversion. Here, we harmonize multiple data sources, including several from LANDFIRE, to report a CONUS-wide assessment of fire regime departure based on fire frequency (in grass and shrublands) and fire severity frequency (in forests). By using a standardized metric of departure, we highlight areas vulnerable to ecosystem loss and identify opportunities for restorative management action.