This legislation, titled the National Quantum Initiative Reauthorization Act of 2026, reauthorizes and expands the existing National Quantum Initiative Act. Its core purpose is to strengthen the United States' leadership in quantum information science, engineering, and technology (QISET) by fostering a robust domestic ecosystem, developing a skilled workforce, and securing critical supply chains. The bill broadens the scope of the National Quantum Initiative Program to encompass research development, demonstration, and standards engagement, involving a wider array of partners including small businesses and strategic allies. It updates definitions to include terms like "foreign country of concern," "foreign entity of concern," and various quantum applications, emphasizing national security and economic competitiveness. The National Quantum Coordination Office's responsibilities are expanded to include tracking and promoting policies for the U.S. quantum workforce, supply chain, and industry. The Subcommittee on Quantum Information Science will now include additional federal agencies and is tasked with identifying potential quantum use cases for federal missions and facilitating interagency partnerships. The National Quantum Initiative Advisory Committee's duties are enhanced, requiring annual evaluations of the program's effectiveness, progress, and usefulness, with detailed reports and recommendations submitted to Congress. A new mandate establishes an International Quantum Cooperation Strategy to forge collaborative partnerships, promote standards integrity, and safeguard quantum research from malign foreign influence. Federal agencies are authorized to conduct prize challenges to accelerate the development of quantum applications and algorithms. The National Institute of Standards and Technology (NIST) will expand its activities in quantum and post-quantum cryptography, supply chain research, and international standards, including mapping vulnerabilities and recommending mitigation strategies for quantum supply chains. NIST is also directed to establish up to three Quantum Centers through competitive grants, focusing on quantum sensing, manufacturing, and networking, with significant funding authorized through fiscal year 2030. These centers aim to accelerate research, development, deployment, and standardization in QISET. The National Science Foundation (NSF) will expand its quantum research and education initiatives, introducing new student traineeships, fellowships, and cooperative education programs. These efforts are designed to build a diverse workforce pipeline from K-12 through postsecondary education, with a focus on underrepresented groups. A Quantum Reskilling, Education, and Workforce (QREW) Coordination Hub will be established by NSF to address cross-cutting workforce development challenges, disseminate best practices, and facilitate employment opportunities in quantum-related industries. NSF is also authorized to establish quantum testbeds to accelerate the development of viable quantum applications through proof-of-concept testing, demonstrations, and prototyping. A new title is added to the Act, authorizing the National Aeronautics and Space Administration (NASA) to conduct QISET research for space and aeronautics applications. NASA is required to develop a strategy for its quantum activities and may establish initiatives focused on space-based quantum sensing, networking, communications, and computing. Throughout the bill, strong provisions for research security are integrated, consistent with existing legislation, and prohibit funding to institutions with ties to Confucius Institutes or to foreign countries and entities of concern. The Director of the Office of Science and Technology Policy is mandated to review and assess regulatory barriers hindering quantum development and provide recommendations for modernization. Finally, the bill includes a significant change by terminating the National Nanotechnology Program and its associated authorities 180 days after enactment, with a plan for an orderly wind-down. The sunset date for the core authorities of the National Quantum Initiative Act is extended to December 30, 2034, ensuring continued federal support for quantum advancements.