Lieutenant Commander (United States)

Lieutenant commander (LCDR) is a mid-ranking officer rank in the United States Navy, the United States Coast Guard, the United States Public Health Service Commissioned Corps, and the National Oceanic and Atmospheric Administration Commissioned Officer Corps (NOAA Corps), with the pay grade of O-4 and NATO rank code OF-3. The predecessors of the NOAA Corps, the United States Coast and Geodetic Survey Corps (1917-1965) and the Environmental Science Services Administration Corps (1965-1970), also used the lieutenant commander rank, and the rank is also used in the United States Maritime Service and the United States Naval Sea Cadet Corps. Lieutenant commanders rank above lieutenants and below commanders, and rank is equivalent to a major in the other United States Army, United States Air Force, and United States Marine Corps.

Promotion to lieutenant commander in the U.S. Navy is governed by United States Department of Defense policies derived from the Defense Officer Personnel Management Act of 1980. DOPMA guidelines suggest 80% of lieutenants should be promoted to lieutenant commander after serving a minimum of three years at their present rank and after attaining nine to eleven years of cumulative commissioned service.

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