|Comparative military ranks
|Naval officer ranks
Sub-lieutenant is usually a junior officer rank, used in armies, navies and air forces.
In most armies, sub-lieutenant is the lowest commissioned officer rank. However, in Brazil, it is the highest non-commissioned rank, and in Spain, it is the second highest non-commissioned rank.
As a naval rank, a sub-lieutenant ranks below a lieutenant.
In France, a sub-lieutenant (sous-lieutenant) is the junior commissioned officer in the army or the air force. He wears a band in the colour of his corps (e.g. gold for infantry, silver for armoured cavalry, etc.). During the 18th century a rank of sous-lieutenant de vaisseau existed in the French Navy. It was the equivalent of the master's mate rank of the Royal Navy. It is now replaced by the rank of "first ensign" (enseigne de vaisseau de première classe).
An Argentinian sub-lieutenant wears a single silver sun on each shoulder, Brazilian sub-lieutenants are the most senior non-commissioned rank (called Sub-Officer in the Navy and Air force), wearing a golden lozenge. In Mexico, the sub-lieutenant is the most junior officer in the rank scale, and wears a single gold bar. Thai sub-lieutenants and acting sub-lieutenants wear a single star on each shoulder.
The British Army briefly used the rank of sub-lieutenant from 1871 to 1877, replacing the ranks of ensign in the infantry and cornet in the cavalry. In 1877, it was replaced in turn by the rank of second lieutenant, although this had always been used by the Royal Artillery, Royal Engineers, and rifle and fusilier regiments.