| W 100.1 |
Military Intelligence Division (1918-1947) |
| W 27.1 |
Military Prison, Fort Leavenworth (1874-1909) |
| D 216.1 |
Military Sealift Command (1970- ) |
| L 38.1 |
Mine Safety and Health Administration (1978- ) |
| I 69.1 |
Mining Enforcement and Safety Administration (1973- 1978) |
| C 1.102 |
Minority Business Development Agency (1979- ) |
| T 42.1 |
Miscellaneous Division (1888-1906) |
| W 31.1 |
Mississippi River Commission (1879-1947) |
| W 32.1 |
Missouri River Commission (1884-1902) |
| P 9.1 |
Money Orders Division (1864-1951) |
| LC 40.1 |
Motion Picture, Broadcasting, and Recorded Sound Division (1942- ) |
| I 37.1 |
Motion Pictures Division (1935-1939) |
| W 88.1 |
Motor Transport Corps (1918-1920) |
| P 21.1 |
Motor-Vehicle Service Division (1924-1941) |
| W 30.1 |
Mounted Service School (1887-1947) |
| M 401.1 |
Munitions Board |
| M 5.1 |
Munitions Board (1947-1949) |
| LC 12.1 |
Music Division (1902-1940, 1949- ) |
| Pr 33.901 |
Mutual Security Agency (1951-1953) |
