MOS Codes in the Vietnam era - from Charles Carter - July 2012

MOS Military Occupation Specialty The U S Army used alpha-numeric codes to identify a soldier's Military Occupational Specialty. Basically, an "MOS" is the job in which the GI was stringently schooled and trained to perform. The MOS that a soldier was trained, tested and qualified in, was called the PMOS (primary MOS). The DMOS (duty MOS) was the job description they were actually performing at any particular time. MOS coding systems were different for Enlisted Personnel, Warrant Officers and Commissioned Officers: Enlisted MOS codes consisted of five Alpha / Numeric characters. The first three indicated a job description. The last two digits indicated rank or relative level of expertise. xxx10 = (E1-E3) xxx20 = Specialist 4 /Corporal (Specialist 4th Class, E-4) xxx30 = Specialist 5 (non troop handling E-5) xxx40 = Non-Commissioned Officer (Sergeant E-5, Staff Sergeant E-6, Sergeant First Class E-7) xxx50 - Senior Non-Commissioned Officer (E-8, E-9) When the individual had advanced schooling or held a special training skill, a "Special Qualification Identifier" (SQI) replaced the last digit of his MOS. This letter indicated the individual's special qualification. (e.g., If an MOS was 11B4P, this indicated that the soldier was an Infantryman [11B] NCO [4] Parachutist [P].) Warrant Officer MOS codes were 5 Alpha / Numeric digits. The first four Numbers the Officers position, the last character was available for an SQI suffix letter. Commissioned Officer MOS codes were all numerical. Four digits indicated his MOS (e.g., 1542, Infantry Officer) A PREFIX SQI numerical digit was added to indicated a special qualification (e.g., 71542, Jump-qualified Infantry Officer). Special Note to Post Vietnam Personnel: During the 1980s, The U.S. Army changed the MOS code structure. So, the MOS codes which you see here are now history.