This report, the 2021 U.S. Geothermal Power Production and District Heating Market Report, was developed by the National Renewable Energy Laboratory (NREL) and Geothermal Rising (previously the Geothermal Resources Council, or GRC), with funding support from the Geothermal Technologies Office (GTO) of the U.S. Department of Energy (DOE). This report provides policymakers, regulators, developers, researchers, engineers, financiers, and other stakeholders with up-to-date information and data reflecting the 2019 geothermal power production and district heating markets, technologies, and trends in the United States. The report presents analysis of the current state of the U.S. geothermal market and industry for both the power production and district heating sectors, with consideration of developing power projects. Geothermal heat pumps, although a key technology in the wider use of geothermal resources, are outside the scope of this report. In addition, the report evaluates the impact of state and federal policy, presents current research on geothermal development, and describes future opportunities for the U.S. geothermal market and industry.