As the United States moves towards a more electrified and carbon-free future, energy storage will be key to providing reliability and grid flexibility. A range of energy storage technologies (including battery storage, flywheels, and pumped hydropower) are being explored for different use cases and geographic locations with an overarching goal of supporting state and federal decarbonization and resilience efforts. Efforts are also underway to determine the potential for long-duration energy storage including iron-air batteries and clean hydrogen. State Energy Offices play an important role in advancing the research, development, and demonstration (RD&D) of these energy storage technologies through grant and incentive programs, cost-benefit analysis and market assessment studies, state energy storage roadmaps, engagement with investor-and-consumer owned utilities, and collaboration with the U.S. Department of Energy (DOE) and private sector.