NNSA has established a system where federally-run site offices oversee the Management & Operating contractors for each of NNSA's eight sites. These site offices provide the necessary communication between federal and contractor employees as well as oversight to improve management procedures.  

• Kansas City Site Office
  The Kansas City Site Office (KCSO) stewards NNSA's Kansas City Plant, the principal nonnuclear production site within the nuclear weapons complex. Its mission is to lead and direct the administration of its management & operating contract. The site office provides oversight and assessment, weapons programmatic guidance, security direction, and management for NNSA's Quality Assurance program. It is also actively involved in the Reimbursable Work program, which unifies KCSO with other federal agencies, and the Six Sigma program that achieves operations processes through the mission of continuous improvement. The KCSO is located in Kansas City, Missouri.
• Livermore Site Office
  The Livermore Site Office (LSO) oversees NNSA's Lawrence Livermore National Laboratory, one of NNSA's weapons design laboratories. LSO is responsible for administering the performance based contract which oversees the lab. Additionally, the site office promotes national nuclear safety, executes assigned NNSA and Department of Energy programs and conducts oversight of work performed by industrial contractors and grantees in support of NNSA's requirements and priorities. The LSO is located in Livermore, California.
• Los Alamos Site Office
  The Los Alamos Site Office (LASO) manages the resources of NNSA's Los Alamos National Laboratory, one of NNSA's weapons design laboratories. LASO aims to minimize safety risks for federal and contractor employees as well as fosters quality and continuous improvement in the lab's operations. The LASO is located in Los Alamos, New Mexico.
• Nevada Site Office
  The Nevada Site Office (NSO) oversees operations for NNSA's Nevada Test Site. Due to the current moratorium on nuclear weapons testing, NSO's primary mission is to support stockpile stewardship, environmental management, emergency response, and technology diversification. The NSO is located in Las Vegas, Nevada.
• Pantex Site Office
  The Pantex Site Office (PXSO) has oversight responsibility for the NNSA's Pantex Plant, which is the nation's only nuclear weapons assembly and disassembly facility. Its mission is to provide on-site management, day-to-day oversight and surveillance for the Pantex Plant. The PXSO works closely with the plant's Management and Operating contractor to ensure safe, secure, and cost-effective performance. The PXSO is located at the Pantex Plant 17 miles northeast of Amarillo, Texas. 
• Sandia Site Office
  The Sandia Site Office (SSO) oversees NNSA's Sandia National Laboratories, the laboratories responsible for the development, testing, and production of specialized nonnuclear components. The SSO is located in Albuquerque, New Mexico.
• Savannah River Site Office
  The Savannah River Site Office (SRSO) is responsible for NNSA's Defense Program missions at the Department of Energy's Savannah River Site (SRS). The primary missions are reclamation of previously used tritium reservoirs; receipt, packaging and shipping of reservoirs; recycling, extraction, and enrichment of tritium gas in support of the maintenance of the nuclear weapons stockpile, including the U.S. stockpile of tritium; Limited-Life Component Exchange Reservoir Surveillance and Tritium Extraction in support of the maintenance of the nuclear weapons stockpile. The SRS is also the location where three interrelated facilities will be built and operated to implement the United States' nonproliferation commitment to dispose of its surplus weapon-grade plutonium. These facilities are the Mixed Oxide (MOX) Fuel Fabrication Facility (under construction), the Pit Disassembly and Conversion Facility (PDCF), and the Waste Solidification Building (WSB).  The SRSO is south of in Aiken, South Carolina.  
• Service Center
  NNSA's Service Center serves provides procurement, human resources, and other support services to each of NNSA's site offices. It is located in Albuquerque, New Mexico.
• Y-12 Site Office
  The mission of the NNSA’s Y-12 Site Office (YSO) is to ensure the safe, secure and cost-effective operation of the Y-12 National Security Complex. Y-12 is responsible for ensuring the safety and reliability of the nation’s nuclear weapons stockpile. YSO employees perform program oversight, contract and administrative management, and technical evaluation and assessment to meet this mission.