- Census of Partial Employment, Unemployment, and Occupations56
- Census, 12th, Select Committee on2
- Census, 1940 (16th)1
- Census, Bureau of the46
- Census, Committee on the9
- Centennial of Establishment of Seat of Government in Washington, Committee on2
- Centennial of Louisiana Purchase, Special Committee on3
- Center for Disease Control101
- Central Department1
- Central Housing Committee95
- Central Intelligence Agency86
- Central Pacific and Western Pacific Railroads Commission1
- Central Statistical Board8
- Central Statistical Committee1
- Centralization of Heavy Industry in United States, Special Committee to Investigate, Senate5
- Cessions Committee199
- Chaplains Office of Chief of1
- Charleston Navy-Yard1
- Charts14
- Chemical Corps (Army)51