Battalion A battalion is a military unit with 300 to 1 , 200 soldiers that usually consists of two to seven companies and is commanded by either a lieutenant colonel or a colonel . Several battalions form a regiment or brigade . The nomenclature varies by nationality and by branch of arms , for instance , some armies organize their infantry into battalions , but call battalion - sized cavalry , reconnaissance , or tank units a squadron or a regiment instead . There may even be subtle distinctions within a nation ' s branches of arms , such as a distinction between a tank battalion and an armored squadron , depending on how the unit ' s operational role is perceived to fit into the army ' s historical organization . A battalion is generally the smallest military unit capable of independent operations ( i . e . , not attached to a higher command ) , although many armies have smaller units that are self - sustaining . The battalion is usually part of a regiment , brigade , or group , depending on the organizational model used by that service . The bulk of a battalion will ordinarily be homogeneous with respect to type ( e . g . , an infantry battalion or a tank battalion ) , although there are many exceptions . Every battalion will also include some sort of combat service support , typically organized within a combat support company . The term is Italian in origin , appearing as " battaglione " . The French changed the spelling to " bataillon " , whereupon it directly entered into German . British Army . The term " battalion " is used in the infantry , Royal Electrical and Mechanical Engineers , and Intelligence Corps only . It was formerly used for a few units in the Royal Engineers ( before they switched to regiments ) , and was also used in the now defunct Royal Army Ordnance Corps and Royal Pioneer Corps . Other corps usually use the term " regiment " instead . An infantry battalion is numbered ordinarily within its regiment ( e . g . , 1st Battalion , The Rifles , usually referred to as 1 Rifles ) . It normally has a headquarters company , support company , and three rifle companies ( usually , but not always , A , B and C Companies ) . Each company is commanded by a major , the officer commanding ( OC ) , with a captain or senior lieutenant as second - in - command ( 2IC ) . The HQ company contains signals , quartermaster , catering , intelligence , administration , pay , training , operations and medical elements . The support company usually contains anti - tank , machine gun , mortar , pioneer and reconnaissance platoons . Mechanised units usually have an attached light aid detachment ( LAD ) of the Royal Electrical and Mechanical Engineers ( REME ) to perform field repairs on vehicles and equipment . A British battalion in Theatre of War II had around 845 men in it , and as of 2012 a British battalion has around 650 soldiers . With successive rounds of cutbacks after the war , many infantry regiments were reduced to a single battalion ( others were amalgamated to form large regiments which maintained multiple battalions , e . g . , the Royal Anglian Regiment ) . Important figures in a battalion headquarters include : Battalions of other corps are given separate cardinal numbers within their corps ( e . g . , 101 Battalion REME ) . Battalion group . A battalion group is a military unit based around a battalion . A typical battalion group consists of an infantry or armoured battalion with sub - units detached from other military units acting under the direct command of the battalion commander . Battalion groups may be permanent or temporary formations . Under modern military doctrine battalion groups are being replaced by battlegroups . The key difference between battalion groups and battlegroups is that battlegroups consist of a mixture of sub - units and typically do not include all sub - units of any single battalion . The battalion staff includes the operations officer ( usually a major ) who is also generally the next in command hierarchy after the battalion second in command . Canadian Army . In the Canadian Forces , most battalions are reserve units of between 100 – 200 soldiers that include an operationally ready , field - deployable component of approximately a half - company apiece . The nine regular force infantry battalions are each composed of three rifle companies . Canadian battalions are generally commanded by lieutenant - colonel s , though smaller reserve battalions may be commanded by major s . Those regiments consisting of more than one battalion are : Tactically , the Canadian battalion forms the core of the infantry battle group , which also includes various supporting elements such as armour , artillery , combat engineer s and combat service support . An infantry battle group will typically be commanded by the commander of the core infantry battalion around which it is formed and can range in size from 300 to 1 , 500 or more soldiers , depending on the nature of the mission assigned . Colombian Army . In the Colombian Army , a battalion usually has a strength of 1 , 200 to 1 , 300 men , and is divided in companies . Normally it is commanded by a Lieutenant Colonel or a Colonel . Counter Insurgency Battalions are the exception as they usually have around 300 soldiers , and are commanded by a Major . Two or more battalions form a Brigade . Battalions are numbered ordinarily and according to its specialty : Swiss Army . With the major reform of its Armed Forces in 2004 , the Swiss Army abandoned the old regimental system and adopted a combat team approach centred on battalions as the building blocks of mission - oriented task forces . Battalion sizes vary between branches . For example , an infantry battalion has a nominal strength of 1 , 224 men . United States . United States Army . In the United States Army , a battalion is a unit composed of a headquarters and two or more batteries , companies or troops . They are normally identified by ordinal numbers ( 1st Battalion , 2nd Squadron , etc . ) and normally have subordinate units that are identified by single letters ( A Battery , A Company , A Troop , etc . ) . Battalions are tactical and administrative organizations with a limited capability to plan and conduct independent operations and are normally organic components of brigades , groups , or regiments . A US Army battalion includes the battalion commander ( lieutenant colonel ) , his staff , and headquarters , the command sergeant major ( CSM ) , and usually 3 – 5 companies , with a total of 300 to 1 , 200 soldiers . A regiment consists of between two and six organic battalions , while a brigade consists of between three and seven separate battalions . During the American Civil War , an infantry or cavalry battalion was an ad hoc grouping of companies from the parent regiment ( which had ten companies , A through K , minus J as described below ) , except for certain regular infantry regiments , which were formally organized into three battalions of six companies each ( numbered 1 – 6 per battalion vice sequential letter designations ) . After 1882 , cavalry battalions were renamed squadrons and cavalry companies were renamed troops . Artillery battalions typically comprised four or more batteries , although this number fluctuated considerably . During World War II , most infantry regiments consisted of three battalions ( 1st , 2nd , and 3rd ) with each battalion consisting of three rifle companies and a heavy weapons company . That is , rifle companies A , B , C along with heavy weapons company D were part of the 1st battalion , rifle companies E , F , G , and heavy weapons company H constituted the 2nd battalion , and rifle companies I , K . L , and heavy weapons company M were in the 3rd . There was no J company : the letter " J " was traditionally not used because in 18th and 19th century old - style type the capital letters " I " and " J " looked alike and were therefore too easily confused with one another . It was common for a battalion to become temporarily attached to a different regiment . For example , during the confusion and high casualty rates of both the Normandy landings and the Battle of the Bulge , in order to bolster the strength of a depleted infantry regiment , companies and even battalions were moved around as necessary . From the 1960s through the early 1980s , a typical maneuver ( infantry or tank ) battalion had five companies : Headquarters and Headquarters Company ( HHC ) and A , B , and C Companies , plus a Combat Support Company , CSC , with a scout platoon , 4 . 2 inch " heavy " mortar platoon , along with other elements that varied between organizations . These included heavy anti - tank TOW missile platoons , ground surveillance radar sections , man - portable anti - aircraft missile sections and others . Beginning in the early to mid - 1980s some elements of the combat support companies ( the mortar and scout platoons ) were merged into the Headquarters Company with the staff and support elements , others were moved to their parent type organization ( ground surveillance radar and air defense ) , and in infantry battalions the heavy anti - tank missile platoon was organized as a separate company ( E Company ) . In the late 1980s , there was a fourth " line " company added ( D Company ) in most infantry and tank battalions . In this older structure , U . S . Army mechanized infantry battalions and tank battalions , for tactical purposes , cross - post companies to each other , forming a battalion - sized task force ( TF ) . Starting in 2005 – 2006 with transformation , the U . S . Army mechanized and tank battalions were reorganized into combined arms battalions ( CABs ) . Tank battalions and mechanized infantry battalions no longer exist . These new combined arms battalions are modular units , each consisting of a headquarters company , two mechanized infantry companies , two armor companies , and a forward support company attached from the battalions parent brigade support battalion . This new structure eliminated the need to cross - post ( or as it is more commonly referred to , cross - attach ) companies between battalions ; each combined arms battalion was organically composed of the requisite companies . At a higher level , each heavy brigade is composed of two CABs , an armored reconnaissance squadron , a fires battalion ( field artillery ) , a special troops battalion ( STB ) , and a brigade support battalion ( BSB ) . United States Marine Corps . A United States Marine Corps battalion includes the battalion headquarters , consisting of the commanding officer ( usually a lieutenant colonel , sometimes a colonel ) , an executive officer ( the second - in - command , usually a major ) , the sergeant major , and the executive staff ( S - 1 through S - 4 and S - 6 ) . The battalion headquarters is supported by a Headquarters and Service Company ( Battery ) . A battalion usually contains 2 – 5 organic companies ( batteries in the artillery ) , with a total of 500 to 1 , 200 marines in the battalion . A regiment consists of a regimental headquarters , a headquarters company ( or battery ) , and two to five organic battalions ( Marine infantry regiments – three battalions of infantry ; Marine artillery regiments – three to five battalions of artillery ; Marine combat logistics regiments – one to three combat logistics battalions ) . In the USA Marine Corps , the brigade designation is used only in " Marine Expeditionary Brigade " ( MEB ) . A MEB is one of the standard Marine air - ground task force s ( MAGTF ) , is commanded by a brigadier general or major general , and consists of command element , a ground combat element ( usually one reinforced Marine infantry regiment ) , an aviation combat element ( a reinforced Marine Aircraft Group including rotary wing , fixed wing , and tiltrotor aircraft ) , and a combat logistics element ( a Marine Combat Logistics Regiment , which includes naval construction force [ Seabees ] and naval medical elements ) . In the U . S . Marine Corps , an infantry or " rifle " battalion typically consists of a Headquarters and Service Company ( H & S Co . ) , three rifle , or " line " , companies ( designated alphabetically A through M depending upon which battalion of the parent regiment to which they are attached ) and a weapons company . Weapons companies do not receive a letter designation . Marine infantry regiments use battalion and company designations as described above under World War II , with company letters D , H , and M not normally used but rather held in " reserve " for use in augmenting a fourth rifle company into each battalion as needed . United States Marine Corps infantry battalions are task organized into battalion landing teams ( BLTs ) as the ground combat element ( GCE ) of a Marine Expeditionary Unit ( MEU ) . A " standard " U . S . Marine infantry battalion is typically supported by an artillery battery and a platoon each of tanks , amphibious assault vehicles , light armored reconnaissance vehicles , reconnaissance marines , and combat engineers . The battalion structure is designed to readily expand to include a fourth rifle company , if required , as described above under battalion organization . Often Air Naval Gunfire Liaison Company ( ANGLICO ) officers are assigned to the battalion , to coordinate naval gunfire support . United States Navy . The United States Navy has Construction Battalions and Navy Cargo Handling Battalions USSR . Soviet Armed Forces . In the Soviet Armed Forces a motorised rifle battalion could be mounted on either BTR armoured personnel carrier s or BMP infantry fighting vehicle s , with the former being more numerous by the late 1980s . Both consisted of a battalion headquarters of 12 and three motorised rifle companies of 110 personnel each and a number of combat support units : a mortar battery consisting of eight 120mm 120 - PM - 43 mortar s or automatic 82mm 2B9 Vasilek s , an air defense platoon with nine MANPAD s , either the SA - 7 Grail , SA - 14 Gremlin or SA - 16 Gimlet , and an automatic grenade launcher platoon with six 30mm AGS - 17 launchers . The BTR battalion also featured an anti - tank platoon with four AT - 3 Sagger or AT - 4 Spigot launchers and two 73mm SPG - 9 recoilless gun s ; BTR units on high - readiness status sometimes had six missile launchers and three recoilless guns . Both featured the same support units as well , with a signal platoon , supply platoon , repair workshop and medical aid station . The addition of the antitank platoon meant a BTR battalion at full strength was 525 , while a BMP battalion consisted of 497 personnel . Prior to the late 1980s Soviet tank battalions consisted of three tank companies of 13 T - 64 , T - 72 or T - 80 tanks , along with a battalion headquarters mounted in a command tank and a headquarters and service platoon , for a total of 165 personnel and 40 tanks ; battalions using the older T - 54 , T - 55 or T - 62 s tanks had 31 or 40 additional enlisted personnel . However forces in Eastern Europe began to standardize to a smaller formation with 135 personnel and 31 tanks total , with each tank company consisting of 10 tanks total .