In the United States Army, U.S. Marine Corps, U.S. Air Force and U.S. Space Force, lieutenant colonel is a field-grade military officer rank, just above the rank of major and just below the rank of colonel. It is equivalent to the naval rank of commander in the other uniformed services.
The pay grade for the rank of lieutenant colonel is O-5. In the United States armed forces, the insignia for the rank are a silver oak leaf, with slight stylized differences between the version of the Army and the Air Force and that of the Navy and the Marine Corps.
Promotion to lieutenant colonel is governed by Department of Defense policies derived from the Defense Officer Personnel Management Act (DOPMA) of 1980, for officers in the Active Component, and its companion Reserve Officer Personnel Management Act (ROPMA), for officers in the Reserve Component (e.g., Reserve and National Guard). DOPMA guidelines suggest that 70 percent of majors be promoted to lieutenant colonel after serving at least three years at their present rank and after 15–17 years of cumulative commissioned service.
The U.S. Army uses the three letter abbreviation "LTC," while the United States Marine Corps and U.S. Air Force use the abbreviations of "LtCol" and "Lt Col" (note the space), respectively. These abbreviation formats are also outlined in The Naval Institute Guide to Naval Writing and in Air Force Handbook 33-337 (AFH 33-337), The Tongue and Quill.
The United States Government Publishing Office recommends the abbreviation "LTC" for U.S. Army usage, "LtCol" for Marine Corps usage, and "Lt. Col." for the Air Force. The Associated Press Stylebook recommends the abbreviation "Lt. Col." for the Army, Marine Corps, and Air Force.
Slang terms for the rank historically used by the U.S. military include "light colonel", "short colonel", "light bird", "half colonel", "bottlecap colonel" (referring to the silver oak leaf insignia), and "telephone colonel" (from self-reference as "colonel" when using a telephone).
The rank of lieutenant colonel has existed in the British Army since at least the 16th century and was used in both American colonial militia and colonial regular regiments. The Continental Army continued the British and colonial use of the rank of lieutenant colonel, as the second-in-command to a colonel commanding a regiment. The lieutenant colonel was sometimes known as "lieutenant to the colonel."
In British practice, regiments were actually commanded by their lieutenant colonels, as the colonel was a titular position  (with the incumbent absent from the regiment serving as a senior staff officer, a general officer, or as a member of the nobility). Since the British colonel was not a "combat" officer, beginning in May 1778 to simplify prisoner of war exchanges, American regiments began to eliminate colonels by attrition and replace them with a lieutenant colonel commandant. The conversion was never completely effected and some regiments remained commanded by colonels throughout the war. From 1784 until 1791, there was only one lieutenant colonel in the US Army (Josiah Harmar), who acted as the army's commanding officer.
In the Continental Army aides to the Commander in Chief, viz., Lieutenant General George Washington, were lieutenant colonels. Additionally, certain officers serving under the Adjutant General, Inspector General, and Judge Advocate General, ranked as lieutenant colonels.
During the 19th century, lieutenant colonel was often a terminal rank for many officers, since the rank of "full colonel" was considered extremely prestigious reserved only for the most successful officers. Upon the outbreak of the Civil War, the rank of lieutenant colonel became much more common and was used as a "stepping stone" for officers who commanded small regiments or battalions and were expected, by default, to be promoted to full colonel once the manpower of a regiment grew in strength. Such was the case of Joshua Lawrence Chamberlain, who commanded a Maine regiment as both a lieutenant colonel and later as a colonel.
After the Civil War ended, those officers remaining in the United States Armed Forces found lieutenant colonel to again be a terminal rank, although many lieutenant colonels were raised to higher positions in a brevet status. Such was the case with George A. Custer, who was a lieutenant colonel in the regular army, but held the brevet rank of major general.
The 20th century saw lieutenant colonel in its present-day status although, during the 1930s, many officers again found the rank to be terminal as the rank of colonel was reserved for only a select few officers.
In the United States Army and the United States Marine Corps (USMC), a lieutenant colonel typically commands a battalion- or squadron-sized unit (300 to 1,200 Soldiers or Marines), with a major as executive officer (XO) and a command sergeant major or sergeant major (USMC) as principal non-commissioned officer (NCO) or senior enlisted adviser (SEA). A lieutenant colonel may also serve as a brigade/brigade combat team, regiment/regimental combat team, Marine Aviation Group (MAG), Marine Expeditionary Unit (MEU), or battalion task force executive officer. Lieutenant colonels routinely serve as principal staff officers, under a colonel as chief of staff, on a general staff ("G" staff) of a division, Marine Expeditionary Brigade (MEB), Marine Aircraft Wing (MAW), or Marine Logistics Group (MLG). These staff positions include G-1 (administration and personnel), G-2 (intelligence), G-3 (operations), G-4 (logistics), G-5 (planning), G-6 (computers and communications), G-9 (Civil Affairs). "The G-n" may mean either a specific staff section or the staff officer leading a section. Lieutenant colonels may also be junior staff at a variety of higher echelons.
In the United States Air Force, a lieutenant colonel is generally a squadron commander in the operations group, mission support group, or maintenance groups, or a squadron commander or division chief in a medical group. The lieutenant colonel also may serve as a Deputy Commander for Operations (DO) in a squadron in the operations group before assuming command of his or her own squadron (this is common for aeronautically rated officers in flying units), or as a deputy commander of a squadron in the maintenance, mission-support, or medical group. Lieutenant colonels may serve also on general staffs and may be the heads of some wing staff departments. Senior lieutenant colonels occasionally serve as group commanders, most commonly in units of the Air Force Reserve Command and the Air National Guard.
In U.S. Army ROTC detachments, the commander is typically a lieutenant colonel, with several majors, captains, and non-commissioned officers serving as assistants. In the U.S. Air Force, Air Force ROTC detachments may be commanded by full colonels or lieutenant colonels, depending on the size of the detachment and the size of the associated college or university.
The rank of lieutenant colonel is also used by many large American municipal police departments, county sheriff's offices/departments, state highway patrols, state police, and other law-enforcement agencies for officers in senior administrative positions. The rank is not always called "lieutenant colonel"; and in many cases—especially in municipal police agencies—another term, such as "assistant chief" or "commander", is used, and only the insignia are retained. In some organizations, however, especially state police agencies, both the title and insignia are used. Occasionally, the rank is used with, rather than instead of, an official title. For example, in the Texas Department of Public Safety, the head of the agency's patrol division is titled "Chief of the Highway Patrol" but holds the rank of a lieutenant colonel: this officer therefore is called "lieutenant colonel," not "chief".
Notable American lieutenant colonels
- (U.S. Army)
- Robert L. Bacon (U.S. Army)
- Aaron Burr (Continental Army)
- James Pratt Carter (U.S. Army)
- Joshua Chamberlain (U.S. Army) Medal of Honor recipient
- Ernest Childers (U.S. Army) Medal of Honor recipient
- Jerry Coleman (U.S. Marine Corps)
- Robert G. Cole (U.S. Army) Medal of Honor recipient
- David P. Cooley (U.S. Air Force)
- Philip Corso (U.S. Army)
- Bruce P. "Snake" Crandall (U.S. Army), Medal of Honor recipient for his actions at Ia Drang.
- George Armstrong Custer (U.S. Army)
- James Harold "Jimmy" Doolittle (U.S. Air Force), Medal of Honor recipient for his raid on Tokyo
- Tammy Duckworth (U.S. Army), United States Senator (D-Illinois)
- Joni Ernst (Iowa Army National Guard), United States Senator (R-Iowa)
- Rick Francona (U.S. Air Force)
- John C. Fremont (U.S. Army)
- Gregory D. Gadson (U.S. Army) bilateral above-the-knee amputee, occasional actor and motivational speaker.
- Virgil I. "Gus" Grissom (U.S. Air Force)
- Dave Grossman (U.S. Army) professor of psychology and military science, author and speaker
- David "Bull" Gurfein (U.S. Marine Corps)
- Iceal Hambleton (U.S. Air Force)
- Alexander Hamilton (Continental Army)
- Anthony B. Herbert (U.S. Army)
- Christopher B. Howard (U.S. Air Force)
- Lisa Jaster (U.S. Army), first female USAR officer to become a Ranger School graduate.
- Shawna R. Kimbrell (U.S. Air Force), First female African-American fighter pilot
- Gus Kohntopp (U.S. Air National Guard)
- John Laurens (Continental Army)
- (U.S. Marine Corps), Spokesperson for International Unified Taekwando
- Bruce R. McConkie (U.S. Army) apostle, The Church of Jesus Christ of Latter-day Saints
- Bob McDonnell (U.S. Army) Former Republican Attorney General and Governor of Virginia.
- Amy McGrath (U.S. Marine Corps) political candidate, first female pilot to fly the F/A-18 on a combat mission.
- Hal Moore (U.S. Army) Famous for his actions at Ia Drang
- Michael Mori (U.S. Marine Corps) lawyer and military judge (retired), known for representing David Hicks.
- Dick Muri (U.S. Air Force)
- Oliver North (U.S. Marine Corps)
- Ellison S. Onizuka (U.S. Air Force)
- Ralph Peters (U.S. Army)
- Rob Riggle (U.S. Marine Corps)
- William R. Rowley (U.S. Army)
- Richard Scheuring (U.S. Army)
- Francis R. Scobee (U.S. Air Force)
- John Shimkus (U.S. Army) U.S. Representative from Illinois
- Ronald Speirs (U.S. Army)
- Michael Strobl (U.S. Marine Corps)
- (U.S. Army)
- Tench Tilghman (Continental Army)
- William Travis (Texas Militia)
- Matt Urban (U.S. Army)
- John Paul Vann (U.S. Army)
- Alexander Vindman (U.S. Army)
- David P. Weber (Maryland State Guard), lawyer and certified fraud examiner, revealed nation-state hacking by the Chinese PLA and Russian FSB of U.S. Stock Exchanges
- Allen West (U.S. Army) former Republican Congressman (FL-22)
- Ed White (U.S. Air Force)
- Earl Woods (U.S. Army)
- Shenk, Robert; The Naval Institute Guide to Naval Writing, 3rd ed.; US Naval Institute Press, Annapolis, MD; c2011; ISBN 1591148227 ISBN 9781591148227
- "Preliminary-cloth.indd" (PDF). Retrieved 27 April 2012.
- Jack (21 May 2009). "AP Style Book". Apstylebook.blogspot.com. Retrieved 27 April 2012.
- "The Continental Army". U.S. Army Center of Military History (p. 13). 1 May 1982. Retrieved 3 July 2016.
- "History of the lieutenant colonel rank". Usmilitary.about.com. 9 April 2012. Retrieved 27 April 2012.
- "The Continental Army". U.S. Army Center of Military History (p. 13 ff.). 1 May 1982. Retrieved 3 July 2016.
- "The Continental Army". U.S. Army Center of Military History (p. 48). 1 May 1982. Retrieved 3 July 2016.
- "The Continental Army". U.S. Army Center of Military History (pp. 127–128 ff.). 1 May 1982. Retrieved 3 July 2016.
- "The Continental Army (pp. 128 & 145)". U.S. Army Center of Military History. 1 May 1982. Retrieved 3 July 2016.
- "Lieutenant-Colonel And Brevet Major-General George A. Custer, U.S.A". All-biographies.com. Retrieved 27 April 2012.
- "Brevet Rank In The Civil War". Civilwarhome.com. Retrieved 27 April 2012.
|Pay grade / branch of service||Officer
|Army||CDT / OC||2LT||1LT||CPT||MAJ||LTC||COL||BG||MG||LTG||GEN||GA||GAS|
|Marine Corps||Midn / Cand||2ndLt||1stLt||Capt||Maj||LtCol||Col||BGen||MajGen||LtGen||Gen|||||
|Navy||MIDN / OC||ENS||LTJG||LT||LCDR||CDR||CAPT||RDML||RADM||VADM||ADM||FADM||AN|
|Air Force||Cdt / OT / OC||2nd Lt||1st Lt||Capt||Maj||Lt Col||Col||Brig Gen||Maj Gen||Lt Gen||Gen||GAF|||
|Space Force||Cdt||2nd Lt||||||Maj||Lt Col||Col||||Maj Gen||Lt Gen||Gen|||||
|Coast Guard||CDT / OC||ENS||LTJG||LT||LCDR||CDR||CAPT||RDML||RADM||VADM||ADM|||||
| No universal insignia for officer candidate rank; Navy candidate insignia shown|
Official 1945 proposal for General of the Armies insignia; John J. Pershing's GAS insignia: ; George Dewey's Admiral of the Navy insignia:
 Rank used for specific officers in wartime only, not permanent addition to rank structure
 Grade is authorized by the U.S. Code for use but has not been created
 Grade has never been created or authorized
United States warrant officer and commissioned warrant officer ranks
| Grade inactive|
 Grade is authorized for use by U.S. Code but has not been created