Sergeant first class is the first enlisted rank in the U.S. Army to be selected by the centralized promotion system. As such, it is considerably more difficult to achieve than the previous ranks. A sergeant first class is the first enlisted rank to be considered a senior non-commissioned officer, and a soldier achieving the rank gains not only prestige, but several benefits due to the position. For example, a sergeant first class cannot be demoted by standard non-judicial punishment. To demote a senior non-commissioned officer requires a court martial, or congressional approval, and normally occurs only for offenses that carry heavy punishments.
The rank title of sergeant first class (SFC) existed in the Army from 1890  until 1920 when it was eliminated in an army-wide simplification of enlisted ranks which had grown into a system containing 128 different rank insignia. The rank of SFC was used in several technical branches such as the Army Medical Department and in the Ordnance, Signal, and Quartermaster Corps and was equivalent to the field service ranks at the company/battery/troop "staff" NCO level, such as color sergeant, supply sergeant, or radio sergeant. The Army restored the rank of SFC in 1948 when it replaced technical sergeant.