Updated January 2 2020 Defense Primer Organization of U S Ground Forces Overview The Army is the U S military’s primary ground force Title 10 Subtitle B Part I Chapter 307 of the U S Code addresses the organization of the Army The Marine Corps serves as the Navy’s land-based fighting force Title 10 Subtitle C Part I Chapter 507 Section 5063 addresses Marine Corps composition and functions For the National Guard and Reserves see CRS In Focus IF10540 Defense Primer Reserve Components Organizational Levels of U S Ground Forces The Army and Marine Corps are organized as hierarchies of units with each type of unit commanded by a noncommissioned or commissioned officer of a specific rank These units are described from smallest to largest Squad Team Section A squad is led by a sergeant and consists of 4-12 personnel Squads can be further divided into teams or sections Platoon A platoon—which is led Army or commanded Marines by a lieutenant and includes varying numbers of subordinate squads teams or sections—may vary from 16 to 50 personnel Heavy platoons also have armored vehicles such as tanks or infantry fighting vehicles depending on the type of platoon Company Troop Battery A company is commanded by a captain and includes two to five subordinate platoons usually three or four It has about 100-200 personnel Cavalry air or ground reconnaissance units companies are called troops Army only artillery and air and missile defense companies are called batteries Battalion Squadron A battalion is commanded by a lieutenant colonel and usually includes three to five combat companies and one support company It has about 500 to 900 personnel Cavalry battalions are called squadrons Brigade Combat Team Support Brigades Regiment Group Army brigades are commanded by a colonel and generally are configured as a brigade combat team BCT a functional support brigade FSB or a multifunctional support brigade MFSB Each brigade has about 3 900-4 100 personnel Army cavalry brigades are called regiments some types of support brigades are called groups Marine Corps units at this level also are called regiments The term Marine Expeditionary Brigade MEB refers to a regimental-size task force which is larger than a standard Army brigade Division An Army division is commanded by a major general and includes two to five BCTs usually four an aviation brigade an artillery brigade an engineer brigade and a logistics brigade Army divisions consist of 12 00016 000 personnel Corps Corps are commanded by a lieutenant general and include two to five divisions and numerous support brigades and commands Corps have about 40 000-100 000 personnel The Marines do not have designated corps although a Marine Expeditionary Force MEF is similar in size and also is commanded by a lieutenant general Army An army is the highest command level in a given theater of operations and typically has 100 000-300 000 personnel It is an element of a joint command structure with the Army’s component commanded by a general An Army’s operational theater is established to support one or more corps and includes numerous support brigades and support commands Army Brigades According to the Association of the U S Army’s AUSA Profile of the United States Army 2018 Army Brigades are organized as follows The Brigade Combat Team BCT is the basic combined-arms building block of the Army It is a permanent stand-alone selfsufficient and standardized tactical force of about 4 000 soldiers At present the Army consists of 58 BCTs with 31 BCTs in the Regular Army RA and 27 BCTs in the Army National Guard ARNG The Army has three types of BCTs Infantry BCTs IBCTs Armored BCTs ABCTs and Stryker BCTs SBCTs Infantry BCTs IBCTs include three infantry battalions a reconnaissance and surveillance cavalry squadron a field artillery battalion a brigade engineer battalion and a logistics support battalion IBCTs also are organized to be airborne or air-assault capable As of 2020 the Army will have 13 Active Component and 20 National Guard IBCTs Armored BCTs ABCTs include three armor mechanized infantry battalions an armed reconnaissance cavalry squadron a field artillery battalion a logistics support battalion and a brigade engineer battalion As of 2020 the Army will have 11 Active Component and 5 National Guard ABCTs Stryker BCTs SBCTs are centered on the Stryker an eightwheel-drive armored vehicle SBCTs consist of three infantry battalions a cavalry squadron for reconnaissance and target acquisition a field artillery battalion a brigade support battalion a brigade engineer battalion a military intelligence company an engineer company a signal company an antitank company and a headquarters company As of 2020 the Army will have 7 Active Component and 2 National Guard SBCTs Functional Support Brigades https crsreports congress gov Defense Primer Organization of U S Ground Forces FSBs are designed to plug into operational formations at the Army Service Component Command ASCC corps division or theater level Once deployed these brigades conduct operational or theater-level support There are several types of FSBs including air defense artillery engineers military police cyber signal explosive ordinance disposal medical support and aviation How the Marine Corps Organizes Its Operational Forces Marine Air-Ground Task Force MAGTF The MAGTF is the Marine Corps’ principal organizational construct for conducting missions across the range of military operations MAGTFs consist of command ground combat air combat and support elements Multifunctional Support Brigades Similar to FSBs MFSBs are designed to plug into operational formations but their purpose is to support BCTs There are five types of MFSBs combat aviation combat support sustainment fires and battlefield surveillance and tactical-level task and support Security Force Assistance Brigades SFABs For more information on SFABs see CRS In Focus IF10675 Army Security Force Assistance Brigades SFABs by Andrew Feickert SFABs are capable of conducting Security Force Assistance at the tactical brigade and below level In May 2018 the Army announced it would establish six SFABs—five in the Active Component and one in the Army National Guard ARNG SFABs consist of about 500 soldiers with most being officers and noncommissioned officers NCOs The Army also plans for SFABs to be expanded if the need arises into fully operational BCTs capable of conducting major combat operations In this case SFAB personnel would serve as cadres who would accept the expansion of personnel and equipment required to transform the SFAB into a BCT Marine Corps Adapted from the Congressional Budget Office’s The U S Military’s Force Structure A Primer July 29 2016 pp 45-46 and The U S Military’s Force Structure Fiscal Year 2019 Update to Personnel Numbers and Costs August 15 2018 at https www cbo gov publication 54136 The Marine Corps is a hybrid service with units that engage in combat on the ground and in the air The Marine Corps organizes its forces into task forces each with a command ground combat air combat and support element The largest such task force a Marine expeditionary force MEF includes a ground combat division an air wing and a support group The active component of the Marine Corps has three MEFs including a total of three divisions three air wings and three logistics groups The Marine Corps Reserve contains one division one air wing and one support group although they are not organized into a fourth Marine expeditionary force The MEFs divisions air wings and logistics groups are not standardized units but instead vary in size and composition The Marine Corps currently has 24 Active Component and 8 Reserve Component Infantry Battalions Ground Combat Element GCE The GCE conducts land-based and amphibious operations including offensive defensive humanitarian reconnaissance and security operations Unlike Army BCTs Marine infantry battalions are light-infantry organizations and are not intended to operate independently Typical operations include amphibious assault and raid reconnaissance and surveillance hostage recovery disaster relief and non-combatant evacuation operations Marine Corps Combat Organizations There are four types of MAGTFs the MEF the MEB the Marine Expeditionary Unit MEU and the Special Purpose MAGTF SPMAGTF Marine Expeditionary Force MEFs are the primary warfighting force for larger operations Consisting of 46 000-90 000 Marines and sailors and commanded by a lieutenant general MEFs are composed of a Marine division aircraft wing and logistics group Marine Expeditionary Brigade MEBs are task-organized for specific missions consist of 4 000-16 000 Marines and sailors and are commanded by a brigadier general MEBs have a regimental-size ground combat element and are embarked aboard amphibious assault ships Marine Expeditionary Unit MEUs consist of 2 200 Marines and sailors and are a forward-deployed crisis-response force MEUs deploy as part of an amphibious ready group ARG and are commanded by a colonel Special Purpose MAGTF SPMAGTFs are task-organized to accomplish a specific mission operation or exercise They can conduct a variety of operations ranging from peacetime missions training exercises and responses to contingencies and crises including disaster response and humanitarian assistance Smaller land-based SPMAGTFs—Crisis Response SPMAGTF-CR units—are dedicated to geographic combatant commands and can conduct limited crisis response contingency theater security cooperation and enabling operations Barbara Salazar Torreon Senior Research Librarian Andrew Feickert Specialist in Military Ground Forces IF10571 https crsreports congress gov Defense Primer Organization of U S Ground Forces Disclaimer This document was prepared by the Congressional Research Service CRS CRS serves as nonpartisan shared staff to congressional committees and Members of Congress It operates solely at the behest of and under the direction of Congress Information in a CRS Report should not be relied upon for purposes other than public understanding of information that has been provided by CRS to Members of Congress in connection with CRS’s institutional role CRS Reports as a work of the United States Government are not subject to copyright protection in the United States Any CRS Report may be reproduced and distributed in its entirety without permission from CRS However as a CRS Report may include copyrighted images or material from a third party you may need to obtain the permission of the copyright holder if you wish to copy or otherwise use copyrighted material https crsreports congress gov IF10571 · VERSION 4 · UPDATED