Editing First lieutenant (section)

===U.S. Army, U.S. Marine Corps, U.S. Air Force, and U.S. Space Force===
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In the [[United States Army|U.S. Army]], [[United States Marine Corps|U.S. Marine Corps]], [[United States Air Force|U.S. Air Force]], and [[United States Space Force|U.S. Space Force]], a first lieutenant is a junior [[Officer (armed forces)|commissioned officer]]. It is just above the rank of [[second lieutenant]] and just below the rank of [[Captain (United States O-3)|captain]]. It is equivalent to the rank of [[lieutenant (junior grade)]] in the other [[Uniformed services of the United States|uniformed services]].

Promotion to first lieutenant is governed by Department of Defense policies derived from the [[Defense Officer Personnel Management Act]] of 1980. DOPMA guidelines suggest all "fully qualified" officers should be promoted to first lieutenant. A second lieutenant ([[U.S. uniformed services pay grades|grade]] O-1) is usually promoted to first lieutenant (grade O-2) after 18 months in the Army or 24 months in the Marine Corps and Air Force. The difference between the two ranks is slight, primarily being experience and a higher pay grade. It is not uncommon to see officers moved to positions requiring more experience after promotion to first lieutenant. For example, in the Army and Marine Corps these positions can include leading a specialty [[platoon]], or assignment as the [[executive officer]] for a [[company (military unit)|company]]-sized unit (70–250 soldiers or marines). In the Air Force, a first lieutenant may be a flight commander or section's officer in charge with varied supervisory responsibilities, including supervision of as many as 100+ personnel, although in a flying unit, a first lieutenant is a rated officer (pilot, navigator, or air battle manager) who has just finished training for his career field and has few supervisory responsibilities.