The goal of the Mid-Atlantic U.S. Offshore Carbon Storage Resource Assessment Project (Department of Energy Award Number DE-FE0026087) was to assess offshore carbon storage potential for the mid-Atlantic United States (i.e., New York, New Jersey, Pennsylvania, Delaware, and Maryland). Various publicly available data sets were compiled to define geologic characteristics for Cretaceous- and Jurassic-age sandstone sequences of three mid-Atlantic offshore sub-regions: the Georges Bank Basin, the Long Island Platform, and the Baltimore Canyon Trough. Estimates of CO2 storage capacity indicated a total of 150 to 1136 megatons (Mt), and preliminary reservoir simulations resulted in successful injection of 1 Mt CO2/year sustained for 30 years in single injection wells. This suggests mid-Atlantic U.S. offshore formations can store decades of CO2 from industrial sources in the region. Offshore geologic risk factors include soft sediment deformation, unit continuity, sedimentological and structural features, seismicity, and hydrates. CO2 storage risks include inadequate seals, migration/leakage, and chemical interactions leading to decreased storage. Government, industry, and environmental groups provided addressed next steps needed for future carbon storage project planning and implementation offshore of the mid-Atlantic United States. This project represents an important first step by building the knowledge infrastructure and providing a strong technical basis on which future carbon storage efforts can be built.