In the Royal Navy, United States Navy and United States Coast Guard, a lieutenant commander (lieutenant-commander or Lt Cdr in the RN) is a commissioned officer superior to a lieutenant and inferior to a commander. The corresponding rank in the British Army, Royal Marines, United States Army, United States Air Force and United States Marine Corps is major, and in the Royal Air Force is squadron leader.

A lieutenant commander is a senior department officer on a large ship or shore installation. He or she may be commanding officer or executive officer (second-in-command) of a smaller ship or installation.

Note that unlike similarly-named military ranks (lieutenant colonel, lieutenant general), the title does not indicate a deputy or junior grade of commander, but a senior grade of lieutenant. Lieutenants were commonly put in command of smaller vessels not warranting a commander or captain: such a lieutenant was called a lieutenant commanding or lieutenant commandant in the USN, and a lieutenant in command or lieutenant and commander in the RN. The USN settled on lieutenant commander in 1862, and made it a distinct rank; the RN belatedly followed suit in 1914.

Royal Navy rank insignia

The insignia worn by a Royal Navy lieutenant-commander is two medium gold braid stripes with one thin gold stripe running in between, placed upon a navy blue/black background. The top stripe has the ubiquitous loop used in all RN officer rank insignia. The RAF follows this pattern with its equivalent rank of squadron leader.

Having fewer officer ranks than the army, the RN previously split some of its ranks by seniority (time in rank) to provide equivalence: hence a lieutenant with fewer than eight years' seniority wore two stripes, and ranked with an army captain; a lieutenant of eight years or more wore two stripes with a thinner one in between, and ranked with a major. This distinction was abolished when the rank of lieutenant-commander was introduced, the new rank taking the insignia and army equivalence of a senior lieutenant.

United States Navy rank insignia

While the gold oak leaf collar insignia worn by United States Air Force, Army, and Marine Corps majors are also worn by USN lieutenant commanders, they also wear on various uniforms the two medium and one narrow sleeve and shoulder braid stripe insignia like their counterparts in the Royal Navy, though with a specialty insignia instead of a loop. In this illustration, the inverted star of a Line Officer is used. The pay grade of this rank is O-4.

Unlike its rank equivalents in the Army, Air Force, and Marine Corps - who regard this rank as a Senior Officer (Field Grade) rank - the United States Navy (and Coast Guard) classifies this rank as a Junior Officer (Company Grade) rank, which means that if a lieutenant commander encounters a major on land, the major would actually have authority over him. (This is not the case in the Royal Navy).

See also

• Military unit
• Comparative Military Ranks
• U.S. Navy Officer Rank Insignia