A Sub Lieutenant or sometimes known as Lieutenant (Junior Grade) is a naval rank equivalent to 1st Lieutenant in seniority. A Sub Lieutenant is typically senior to a naval Ensign and junior to a Lieutenant. Sub Lieutenants are addressed by rank and name, thereafter by subordinates as "Sir" or "Ma'am". The rank is usually abbreviated to "SLt./LtJG" or "SLT/LTJG".

Community content is available under CC-BY-SA unless otherwise noted.