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Infantry MOS List | Infantryman Jobs 2023**

U.S. Army Infantry Military Occupational Specialties (MOS)

The U.S. Army, the oldest and most senior branch of the U.S. military, plays a crucial role in national defense. At its core is the infantry, often termed the “backbone” of the Army. Those who belong to this crucial unit are skilled in combat and trained to face the enemy directly. The distinction within this unit is broken down into specific Military Occupational Specialties, commonly referred to as MOS. This article delves into the primary MOS within the infantry, providing a comprehensive understanding of each role.

Understanding Military Occupational Specialties (MOS)

Before diving into the specific roles within the infantry, it’s essential to comprehend the MOS’s overarching concept. An MOS in the U.S. Army refers to the specific job or duty assigned to an individual soldier. Each MOS has a unique code, which is a combination of letters and numbers, representing the nature and level of expertise of the role. The infantry MOS, denoted by the 11 series, has distinct responsibilities and functions.

Army Infantry MOS

Within the infantry are specific MOS that determine a soldier’s precise role and responsibilities. 

There are five Army infantry MOS:

  • 11A – Infantry Officer
  • 11B – Infantryman
  • 11C – Indirect Fire Infantryman
  • 11X – Infantry Enlistment Option
  • 11Z – Infantry Senior Sergeant

Below is a detailed breakdown of each:

11A – Infantry Officer

Role and Responsibilities:

  • Leadership: As the primary leaders of infantry units, they are responsible for directing and strategizing the troop movements and actions.
  • Training: Ensuring the overall readiness and combat effectiveness of the unit.
  • Decision Making: Critical thinking during high-pressure situations is pivotal.

11B – Infantryman

Role and Responsibilities:

  • Combat: Engage in direct contact with adversaries using various weapons.
  • Patrolling: Survey and guard designated areas, ensuring security.
  • Weapons Maintenance: Responsible for the upkeep and readiness of their combat weapons.

11C – Indirect Fire Infantryman

Role and Responsibilities:

  • Specialized Weaponry: Trained to handle and operate indirect fire weapons, especially mortars.
  • Targeting: Determining trajectories and coordinates to ensure accuracy.
  • Teamwork: Often operate in tandem with infantrymen to provide essential support.

11X – Infantry Enlistment Option

Role and Responsibilities:

  • Training: Undergo rigorous training before designation as either 11B or 11C.
  • Adaptability: Must showcase versatility, as their specific MOS will be designated post-training.

11Z – Infantry Senior Sergeant

Role and Responsibilities:

  • Leadership: Lead infantry units and oversee the overall operational functionality.
  • Strategy: Critical input in mission planning and execution.
  • Mentoring: Ensure the growth and development of junior infantry members.

Infantry MOS List 2023

MOS CodeTitleKey Responsibilities
11AInfantry OfficerLeadership, Training, Decision Making
11BInfantrymanCombat, Patrolling, Weapons Maintenance
11CIndirect Fire InfantrymanSpecialized Weaponry, Targeting, Teamwork
11XInfantry Enlistment OptionTraining, Adaptability
11ZInfantry Senior SergeantLeadership, Strategy, Mentoring

Digging Deeper into the Infantry MOS

The U.S. Army Infantry MOS is not just about designations and responsibilities. For soldiers and individuals aspiring to join the infantry, there’s a deeper layer of understanding and preparedness needed. Beyond the primary roles and duties, there are numerous aspects of the Infantry MOS that every soldier should be aware of.

1. Rigorous Training

Every MOS in the infantry requires soldiers to undergo rigorous training, both physically and mentally.

  • Basic Combat Training (BCT): All recruits must first complete BCT where they’ll learn basic soldiering skills.
  • Advanced Individual Training (AIT): Specific to the infantry MOS, this training prepares soldiers for their specific roles within the infantry.
  • Continuous Training: The army emphasizes lifelong learning. Soldiers in infantry MOS regularly engage in refreshers, drills, and new training programs.

2. Potential for Specialized Roles

Beyond the primary MOS, there’s potential for soldiers to branch out into more specialized roles. These can include:

  • Sniper
  • Reconnaissance
  • Ranger
  • Pathfinder
  • Airborne Infantryman

3. Physical and Mental Demands

  • Physical Fitness: Infantry MOS are among the most physically demanding in the Army. Regular fitness tests, long rucks, and tactical drills are common.
  • Mental Resilience: Facing direct combat scenarios requires strong mental fortitude. Soldiers should be prepared for this challenge.

4. Opportunities for Advancement

Like other Army careers, the infantry MOS offers a clear progression path:

  • Promotions: Based on time in service, performance, and continuous learning.
  • Education: The U.S. Army offers various educational benefits that soldiers can leverage for personal and professional development.

5. The Importance of Teamwork

The infantry operates as a cohesive unit. Understanding the essence of teamwork is paramount:

  • Trust: Soldiers must implicitly trust each other, especially in combat situations.
  • Communication: Clear and efficient communication can be the difference between success and failure.

6. Deployment

Infantry MOS soldiers are frequently on the front lines:

  • Combat Zones: They are often the first to be deployed in combat zones or areas of conflict.
  • Duration: Deployments can vary, but soldiers should be prepared for extended periods away from home.

7. Equipment and Weaponry Proficiency

Given the combat-oriented nature of the infantry:

  • Weapon Proficiency: Soldiers need to be adept with a variety of weapons.
  • Equipment Knowledge: Understanding and maintaining equipment, from communications devices to protective gear, is crucial.

The Infantry MOS is a multifaceted career path within the U.S. Army. While the designations and primary responsibilities provide a structural overview, the true essence of the infantry lies in its demands, opportunities, and the ethos of service and sacrifice. Every soldier should be adequately prepared and informed about these deeper layers of the Infantry MOS to serve effectively and build a meaningful career

Stories from the Frontline: Mico Madera & Spc. William Godwin

Mico Madera: The Frontline 11B Infantryman


  • I am Mico Madera, proudly bearing the title of an 11B Infantryman.

Role & Responsibilities:

  • If you ask me about what I do, it’s simple: we shoot, move, communicate, close with, and ultimately, destroy the enemy. 
  • As an 11B infantryman, our main role is doing all the grunt work – from kicking in doors to shooting at close-range targets.


  • What drew me to the 11B MOS was a thirst for adventure and a desire to inject some excitement into my life.
  • The decision didn’t disappoint; the role is filled with adrenaline, discipline, hard work, and immense reliance on teamwork.
  • Being an 11B Army Infantry MOS isn’t just about being on the frontlines; it’s about discipline and collaboration. 
  • In our line of work, we are revered for upholding high standards of discipline, hard work, and always putting the team first.


  • Outside the battleground, one of the most engaging activities I participated in was an operation at the National Training Center (NTC). 
  • We took on fake enemies, advanced to various towns, and moved through regions to overpower the enemy. 
  • The intensity of the simulation, coupled with the real-life feel, was nothing short of exhilarating.


  • Coming from a close-knit family, they swelled with pride when they learned of my decision to join the Army, particularly as an 11B infantryman. 
  • This path hasn’t just been about service; it’s reshaped my personality. 
  • I’ve evolved from being the shy kid on the block to being a confident, decisive individual who’s not afraid to take the lead.

Spc. William Godwin: The Skilled 11C Mortarman


  • I am Spc. William Godwin, a specialized 11C Mortarman.
  • As an 11C Mortarman, my domain is quite different from Mico’s

Role & Responsibilities:

  • I handle the 120 millimeter mortar systems, the 81s, and the 60s, which essentially deal with indirect fire infantry. 
  • This means, that instead of being right in the heart of the action like Mico, I usually hang back. 
  • My job is to use the mortar system to provide supportive fire. 
  • Whether it’s delivering light rounds like loom or more direct support, my role pivots according to the mission at hand.

Motivation & Experience:

  • Though I initially signed up as an 11X, destiny had other plans. 
  • At basic training, I was picked for the role of a mortarman. 
  • One of the best parts of being an 11C is the camaraderie. 
  • The mates I’ve met in this role are some of the best people from all around the U.S., and even beyond. 
  • The concept of ‘battle buddies’ in the Army is real. These are bonds forged in adversity and trust.


  • NTC operations stand out for me too. Post our operations against the mock enemy, OPFOR, we mortars got to do a live fire. 
  • The thrill of shooting different types of ammunition and genuinely executing our roles was a memorable experience.


  • The sense of pride extended to my family as well. 
  • Their joy knew no bounds when I informed them of my active duty status in the Army, especially in the 11 series. 
  • The Army has instilled in me skills that I am certain will serve me well, both during service and in the civilian world afterward.
  • But more than skills, the Army has transformed my very core. I’ve grown from a reserved individual to someone who can command, interact, and lead without any inhibitions. It’s been a transformative journey. 
  • For someone who always felt like an outsider back home, the Army has not only given me a sense of belonging but has also allowed me to see the world and be a part of something larger than myself.

Shared Experiences & Insights

  • Mico Madera and Spc. William Godwin, though serving in different capacities, both embody the essence of the U.S. Army Infantry MOS – service, dedication, and an unwavering commitment to the nation. 
  • Their stories are but a glimpse into the world of the infantry, showcasing the diversity, challenges, and fulfillment that come with serving in the U.S. Army.

Their individual experiences, though rooted in different MOS specialties, converge on themes of growth, camaraderie, and a shared commitment to serve.


The Military Occupational Specialties (MOS) within the infantry are essential for the effective operation of the U.S. Army. 

Each MOS has specific roles and responsibilities, ensuring that the infantry unit remains versatile, adaptive, and always prepared for combat. 

Whether leading a unit or providing indirect fire support, the distinct roles within the infantry MOS are critical to the Army’s success.

 As with all army units, the emphasis on training, adaptability, and readiness remains paramount across all infantry MOS.

George N.