First Lieutenant

First Lieutenant Affiliation Marine Corps Higher Rank Captain Lower Rank Second Lieutenant
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First Lieutenant, usually abbreviated to 1LT, is a junior Marine officer rank, above Second Lieutenant and below Marine Captain.

First Lieutenants generally serve as platoon commanders, as second in command of a company or as adjutants to senior officers. They also serve as commanding officer for small to medium style shipborne detachments.

Marine Corps Officer Ranks
Second Lieutenant	First Lieutenant	Captain	Major	Lieutenant Colonel	Colonel	Brigadier General	Major General	Lieutenant General	General
For the Marine Corps Warrant Officer rank structure click here
For the Marine Corps Enlisted rank structure click here