In the United States Army, Marine Corps, Air Force and Space Force, colonel (//) is the most senior field-grade military officer rank, immediately above the rank of lieutenant colonel and just below the rank of brigadier general. It is equivalent to the naval rank of captain in the other uniformed services.[note 1] By law, an officer previously required at least 22 years of cumulative service and a minimum of three years as a lieutenant colonel before being promoted to colonel. With the signing of the National Defense Authorization Act of 2019 (NDAA 2019), military services now have the authorization to directly commission new officers up to the rank of colonel. The pay grade for colonel is O-6.
|NATO rank code||OF-5|
|Next higher rank||Brigadier general|
|Next lower rank||Lieutenant colonel|
When worn alone, the insignia of rank seen at right is worn centered on headgear and fatigue uniforms. When worn in pairs, the insignia is worn on the officer's left side while a mirror-image reverse version is worn on the right side, such that both of the eagles' heads face forward, to the wearer's front.
The insignia for a colonel is a silver eagle which is a stylized representation of the eagle dominating the Great Seal of the United States (which is the coat of arms of the United States). As on the Great Seal, the eagle has a U.S. shield superimposed on its chest and is holding an olive branch and bundle of arrows in its talons. However, in simplification of the Great Seal image, the insignia lacks the scroll in the eagle's mouth and the rosette above its head. On the Great Seal, the olive branch is always clutched in the eagle's right-side talons, while the bundle of arrows is always clutched in the left-side talons. The head of the eagle faces towards the olive branch, rather than the arrows, advocating peace rather than war. As a result, the head of the eagle always faces towards the viewer's left. Some colonel eagles from the 1920s to the 1950s faced the arrows, though this is no longer done. The full-sized colonel eagle is exactly two inches in diameter from the tips of each wing.
However, when worn as a single insignia with no matching pair, such as on the patrol cap, garrison cap/flight cap, or the front of the Army, Air Force, or Space Force OCP uniform, there is a split between the services on which mirror image of the eagle should be worn. In the United States Army, United States Air Force, and United States Space Force, the eagle is always worn with "the head of the eagle to the wearer's right," with the olive branch clutched in the eagle's right hand talons (see Department of the Army Pamphlet 670-1, paragraph 19-6 [a]). In the United States Navy, United States Marine Corps, United States Coast Guard, NOAA, and the PHSCC, the eagle is worn with "the head facing forward" on the wearer's right side of the garrison cover (see Marine Corps Order P1020.34G, Uniform Regulation, paragraph 4005d). Since respective service's officer insignia is worn on the left side and the rank insignia is worn on the right hand side of the Marine, Navy, Coast Guard and NOAA garrison caps, the eagle is facing to the eagle's left with the olive branch clutched in the eagle's left hand talons, which is a mirror opposite to the wear of the single eagle for Army, Air Force, and Space Force officers.
The United States rank of colonel is a direct successor to the same rank in the British Army. The first colonels in the U.S. were appointed from Colonial militias maintained as reserves to the British Army in the North American colonies. Upon the outbreak of the American Revolutionary War, colonial legislatures would grant commissions to men to raise a regiment and serve as its colonel. Thus, the first U.S. colonels were usually respected men with ties in local communities and active in politics.
With the post-war reduction of the U.S. Army, the rank of colonel disappeared, and was not re-introduced until 1802.
The first insignia for the rank of colonel consisted of gold epaulettes worn on the blue uniform of the Continental Army. The first recorded use of the eagle insignia was in 1805 as this insignia was made official in uniform regulations by 1810.
The rank of colonel was relatively rare in the early 19th century, partly because the U.S. Army was very small, and the rank was usually obtained only after long years of service. During the War of 1812 the Army grew rapidly and many colonels were appointed, but most of these colonels were discharged when their regiments were disbanded at the war's conclusion. A number of other colonels were appointed by brevet – an honorary promotion usually for distinguished service in combat.
The American Civil War saw a large influx of colonels as the rank was commonly held in both the Confederate army and Union Army by those who commanded a regiment. Since most U.S. regiments were state formations and were quickly raised, the colonels in command of the regiments were known by the title "Colonel of Volunteers," in contrast to Regular Army colonels who held permanent commissions.
During the Civil War, the Confederate army maintained a unique insignia for colonel, which comprised three yellow stars worn on the collar of a uniform. Robert E. Lee wore this insignia due to his former rank in the United States Army and refused to wear the insignia of a Confederate general, stating that he would only accept permanent promotion when the Confederacy had defeated the U.S. and achieved its independence.
After the end of the Civil War, the rank of colonel again became rare as the forces of the United States Army downsized and became extremely small. However, many U.S. colonels were appointed in the volunteers during the Spanish–American War, prominent among them Theodore Roosevelt and David Grant Colson.
World War I and World War II saw the largest numbers of colonels ever appointed in the U.S. military. This was mostly due to the temporary ranks of the National Army and the Army of the United States, where those who would normally hold the rank of Captain in the peacetime Regular Army were thrust into the rank of colonel during these two wars.
The Military Promotion System was revised and standardized for all the services in 1980 as a result of passage of the Defense Officer Personnel Management Act.
Contemporary U.S. colonels usually command Army infantry, artillery, armor, aviation, special forces, or other types of brigades or regiments as well as large installations; USMC regiments, Marine Expeditionary Units, Marine Aircraft Groups, or installations such as Marine Corps Bases or Marine Corps Air Stations; USAF groups or wings; and USSF deltas.
An Army colonel typically commands brigade-sized units (4,000 to 6,000 soldiers), with another colonel or a lieutenant colonel as deputy commander, a major as executive officer, and a command sergeant major as a senior non-commissioned officer (NCO) advisor.
An Air Force colonel typically commands a wing consisting of 1,000 to 4,000+ airmen with another colonel as the vice commander, four other colonels as group commanders, which are the major components of wings, and a Chief Master Sergeant (i.e., a "Command Chief") as principal senior NCO enlisted adviser. Colonels are also found as the chief of staff at divisional level-(Army) or Numbered Air Force-level staff agencies.
In the modern armed forces, the colonel's eagle is worn facing forward with head and beak pointing towards the wearer's front. Of all U.S. military commissioned officer rank, only the colonel's eagle has a distinct right and left insignia. All other commissioned officer rank insignia can be worn on either the right or left side.
Colonels are sometimes referred to (but not addressed as) full colonels, bird colonels, or full bird colonels because lieutenant colonels are also referred to and addressed in correspondence as "colonel." Referring to an "O-6", a colonel's pay grade, also may differentiate colonels and lieutenant colonels, who have a pay grade of "O-5". Officers in pay grade O-6 visiting or on temporary assignment to other installations are also accorded "Distinguished Visitor" (DV) status for lodging and other appropriate protocol honors. When flying on military aircraft as either crew or passenger, they are also accorded "Code" status as a "Code 7" in accordance with DoD Flight Information Publication General Planning (DoD FLIP GP).
All Army colonels have attended or otherwise completed via seminar or correspondence a war college or a senior staff college equivalent to study joint warfare and war itself. Most Army colonels receive postgraduate level senior joint professional military education (JPME) at the Army War College in Carlisle, Pennsylvania prior to promotion. The 2009 graduating class was 336 including 198 army officers and the rest divided among other military branches, domestic inter-agency representatives and other foreign military leaders.
A high concentration of USAF and USSF colonels graduate from the Air War College at Maxwell AFB, Alabama via in-residence at Maxwell AFB, while all other USAF colonels will have completed the Air War College via a year-long non-resident seminar program paralleling the in-residence program or the AWC correspondence course program, or a comparable JPME program via the National Defense University (i.e., National War College or Industrial College of the Armed Forces) or the program of another service (i.e., Army War College, College of Naval Warfare at the Naval War College, etc. The AWC program will include participation by officers from various other branches of the U.S. armed forces and NATO and Allied nations. Completion of the Air War College or an equivalent program is a de facto requirement for promotion to colonel in the USAF and USSF, to include the Air Force Reserve and the Air National Guard.
Marine colonels may graduate from the Marine Corps War College or, like all other branches, may receive credit via non-resident attendance at another installation, via correspondence, or will be graduates of an equivalent senior JPME program sponsored by the National Defense University or one of the other U.S. military services.
Some people known as "colonels" are actually recipients of honorary colonel ranks from a state governor and are not officers of the U.S. military. In the 19th century, the honorary colonels were military appointments and they still are nominally appointed to a governor's staff, but without military rights or duties. Famous honorary colonels include Colonel Harland Sanders of KFC fame, a Kentucky colonel; Colonel Tom Parker, Elvis Presley's manager, who received the honor from a Louisiana governor; and Edward M. House, known as Colonel House, a Texas honorary colonel and adviser to President Woodrow Wilson.