Military Occupational Specialty (MOS)Updated: March 17, 2021
What is an MOS or Military Occupational Specialty? The short answer is this is the term used by certain military branches to describe the kinds of jobs you could qualify to do if you join the military.
You can be assigned an MOS prior to basic training, you can “cross-train” out of your MOS under the right circumstances and train for a new military occupational specialty, and you can do a variety of jobs that may be tangential to your specialty while keeping your current MOS.
Basics of the Military Occupational Specialty Code
The first thing most new recruits learn is that most branches of military service have their own jargon to describe an MOS. The United States Army uses MOS, but the Air Force describes its own occupational specialty list as an “Air Force Specialty Code” or AFSC.
The Navy calls its version of this system “ratings” (hence the Navy phrase, “Choose your rate, choose your fate”) but the official term is the Navy Enlisted Classification System for those who enter the Navy in the enlisted grades.
For the purposes of this article, we’ll describe ALL such systems as an MOS, but know that each branch of service has a unique method of classifying military jobs, and assigning them.
Not all military jobs have to do with combat, search and rescue, munitions, parachute operations, etc. But all of them have to have some form of classification code, a standard of training and performance, etc. The MOS is an organizing principle that helps inform how the entire process is managed.
Nuances Of The MOS
An MOS is not necessarily a job description for a single type of work. What does this mean? The Air Force has a Public Affairs specialty code, but Public Affairs can mean many, many things from being a military reporter or photographer to conducting base tours and doing public relations work with civilian agencies who need access to the base.
Public Affairs can involve writing for base newspapers or magazines (famed Gonzo journalist Hunter S. Thompson got his start as an Air Force enlisted member writing for a base newspaper) or assisting other departments on base in handling requests for tours, base access, etc.
When you review a list of military specialties, it’s good to remember that the broader classification of work isn’t necessarily an indicator of the kinds of tasks you personally might be assigned. To give you a better idea of what this means, here’s a (very partial) list of Marine Corps Military Occupational Specialty descriptions:
- Ammunition and Explosive Ordnance Disposal
- 26 — Signals Intelligence/Ground Electronic Warfare
- 27 — Linguist
- 28 — Ground Electronics Maintenance
- 30 — Supply Administration and Operations
- 31 — Traffic Management
- 33 — Food Service
- 34 — Financial Management
- 35 — Motor Transport
- 41 — Marine Corps Community Services
- 43 — Public Affairs
- 44 — Legal Services
- 46 — Combat Camera
- 55 — Music
- 57 — Chemical, Biological, Radiological and Nuclear Defense
- 58 — Military Police and Corrections
- 59 — Electronics Maintenance
Those numbers to the left? They indicate the MOS’s place on the list from #1 to 80 in the number of general MOS options offered by that branch of military service. These jobs are not placed in a rank order such as “From one-to-ten best jobs” but rather as a way to organize and classify the career fields.
And how does the Marine Corps describe the career fields above? Again, keep in mind that these are generalized descriptions, not a list of day-to-day tasks you might be required to accomplish. Consider how the Marine Corps describes the Communications MOS (not listed above):
“Marines in the communications field are frequently called upon to design, install, connect, and operate communication networks. Preventative maintenance on both software and hardware systems is also required across a variety of analog and digital systems.”
Who Gets An MOS?
All recruits will be assigned a job at some point, but when and how depends greatly on circumstances.
You may be offered a chance to select a military job by the recruiter, but some recruits don’t enter boot camp with a “guaranteed job” and must select their MOS or AFSC, etc. at some point during basic training.
You won’t graduate basic training without a job assignment because the next steps for a majority of new recruits and BMT graduates involve a “tech school” or advanced training specifically in the MOS assigned.
That means that Security Forces will attend specific training for that MOS, military IT specialists and linguists will go to their special training schools, etc. In years past, a small number of basic training graduates go directly to their first assignment and receive on-the-job training or have a very short technical training school with a greater emphasis on that OJT.
It is best for most recruits to at least attempt to be given a guaranteed job before shipping out to basic training. This is not always possible, but it is far better to select your MOS in the comfort and stress-free environment of your recruiting office rather than in the high-pressure environment of boot camp.
Who Gets The Best MOS Options?
There’s no way to say it except the most direct way–military recruits who do very well on the Armed Services Vocational Aptitude Battery (ASVAB) have the widest options open to them. ASVAB scores rate each recruit in a variety of areas and those who do poorly in one or more of them find their job options rather limited compared to those who do well in all areas of the test.
The key is to study hard for this test as it is designed to screen out candidates who aren’t cut out for certain jobs that require certain skills. For example, if you are bad with numbers, your ASVAB scores could cut you out of the running for jobs in military finance, certain personnel jobs, etc.
If you score badly on other areas of the test, you may be left out of consideration for certain admin jobs, intel work, or other MOS options that require competitive scores. Ask your recruiter what the best tools to prepare for the ASVAB might be, and be sure to mention what kinds of work you are most interested in doing and which areas of the test might be relevant to those career fields.
Joe Wallace is a 13-year veteran of the United States Air Force and a former reporter for Air Force Television News