Efficient strategies for preparing communities to protect against,respond to, recover from, and mitigateflood hazard are oftenhampered by the lack of information about the position and extentofflood-prone areas. Hydrologic and hydraulic analyses allow toobtain detailedflood hazard maps, but are a computationallyintensive exercise requiring a significant amount of input data,which are rarely available both in developing and developedcountries. As a consequence, even in data-rich environments,officialflood hazard graduations are often affected by extensivegaps. In the U.S., for instance, the detailedfloodplain delineationproduced by the Federal Emergency Management Agency (FEMA)is incomplete, with many counties having nofloodplain mappingat all. In this article we present a mapping dataset containing 100-yearflood susceptibility maps for the continental U.S. with a 90 mresolution. They have been obtained performing a linear binaryclassification based on the Geomorphic Flood Index (GFI). To thebest knowledge of the authors, there are no availableflood-proneareas maps for the entire continental U.S. with resolution lowerthat 30”30” (approximatively 1 km at the equator).