This bill, titled the Small Modular Reactor Commercialization Act of 2025, seeks to update and expand the framework for developing and deploying small modular reactors (SMRs) in the United States. A key provision modernizes the definition of SMRs by increasing their maximum electrical output threshold from 300,000 to 500,000 electrical kilowatts, and the combined rated capacity to 1,500,000 electrical kilowatts. This adjustment ensures that more efficient and powerful modular reactors qualify for existing benefits and regulatory guidance. Furthermore, the bill directs the Nuclear Regulatory Commission and the Department of Energy to revise their guidance to align with these new definitions for both SMRs and microreactors. It also ensures that projects with single reactor unit outputs between 50 and 500 electrical megawatts are not excluded from Department of Energy financial assistance for development, demonstration, or deployment. To further promote domestic SMR capabilities, the legislation mandates the establishment of a Small Modular Reactor Commercialization and Industrialization Competitiveness Working Group within the Department of Energy. This working group will be tasked with identifying SMR technologies, assessing the United States' ability to commercialize them, and attracting long-term manufacturing investment. Its duties also include recommending policy changes to improve U.S. manufacturing of SMR technologies and evaluating workforce readiness for large-scale commercialization. Composed of representatives from various federal agencies, including the Departments of Energy, Defense, and Commerce, the group will submit annual reports to Congress through 2030 detailing its findings and recommendations.