First Lieutenant (O-2) is the second-lowest ranking commissioned officer. It is one grade above the rank of
Second Lieutenant (O-1), one grade below a
Captain (O-3) and promoted after 18 (Army) and 24 months (US Air Force and Marine Corps) of commissioned service. It is a common perception that a First Lieutenant may have increased duties and responsibilities. In reality, the difference between the two ranks of Lieutenant is minimal, the primary difference being experience and an increased paycheck. It is not uncommon to see officers moved to positions requiring more experience sometime after promotion to First Lieutenant. For example, in the Army these positions can include leading a specialty platoon, or assignment as the Executive Officer for a company-sized unit (65-150 Soldiers). In the Air Force a First Lieutenant may be a flight Commander, although in the operations group a first lieutenant is generally a pilot fresh out of undergraduate pilot training and generally has few supervisory responsibilities.
