Carbon capture and storage (CCS) is projected to be an important and cost-effective technology for decarbonizing the economy. Though capturing carbon dioxide (CO2) at its source remains the most expensive component of the infrastructure required to capture, transport, and store CO2, there is large uncertainty and regional variability in estimations of the cost and capacity of CO2 storage in geologic formations. In this study, geospatial modeling is conducted to better characterize the resource potential and costs of CO2 storage in onshore saline formations throughout the conterminous U.S and understand how uncertainty in geologic characteristics, engineering requirements, and financing might impact storage capacity and cost estimates. CO2 storage supply curves are developed for each state and alternate scenarios that seek to capture the range of costs and capacities that might result from geologic and engineering uncertainties. Pessimistic, reference, and optimistic supply curves are implemented in EPRI’s energy-economic model, US-REGEN, and an analysis is conducted to understand the sensitivity of CCS technology deployment to plausible CO2 storage cost and capacity estimates. The supply curves developed in this project constitute a huge improvement in the representation of CO2 storage in US-REGEN. The CO2 storage potential in the conterminous U.S. is found to vastly exceed the modeled storage requirements across all storage supply scenarios. However, the storage potential is not uniformly distributed, and some regions have limited or no storage potential in some or all scenarios. Yet the alternate supply curves have a larger impact on where CO2 is stored than where it is captured. Significant CCS capacity is still deployed in regions with limited storage capacity and any CO2 that cannot be stored locally is transported via pipeline to neighboring regions with available low-cost storage. Moreover, there appears to be sufficient CO2 storage available at costs < $13/tCO2 (excluding transport costs) to meet projected storage requirements through 2050 in the conterminous United States.