The second and third digits denotes the officer's area of specialization within the Line, Staff Corps, LDO or Warrant Officer communities.
The final (fourth) digit denotes the officer's current type of commission.
Fourth Digit
Commission
0
An officer of the Regular Navy whose permanent grade is Ensign or above
1
An officer of the Regular Navy whose permanent status is Warrant Officer or Chief Warrant Officer (NOTE: Warrant Officer (pay grade W-1) is not currently used in the U.S. Navy; all U.S. Navy Warrant Officers are currently commissioned as Chief Warrant Officer 2 (pay grade W-2))
2
A temporary officer of the Regular Navy whose permanent status is enlisted
3
An officer of the Regular Navy who is on the retired list
4
No longer used
5
An officer of the Naval Reserve (NOTE: Exceptions are designators with a 4th digit of 7, 8 or 9)
7
An officer of the Naval Reserve on active duty in the Full Time Support (FTS) Program, previously known as the Training and Administration of the Reserve (TAR) Program; includes officers of the FTS Program rotated to other than FTS billets
8
An officer of the Naval Reserve who was appointed in the Naval Reserve Integration Program from enlisted status or whose permanent status is Chief Warrant Officer, Warrant Officer or enlisted
9
An officer of the Naval Reserve who is on the retired list
Between Fiscal Year 1992 until Fiscal Year 2005, all officers entering the U.S. Navy were awarded a Reserve commission (commissioned as Ensign, USNR). Legislation was signed that all Reserve Officers on full-time Active Duty, previously designated by a "5" in the last digit of the designator, would be converted over to a Regular Navy commission by the close of Fiscal Year 2006.
Today, there is no distinction between USN and USNR Officers, no matter what the commissioning source. All hold the same ranks, have the same responsibilities and authority, and enjoy the same privileges. As part of the U.S. Navy's Active Reserve Integration (ARI) initiative that "operationalized" the Navy's Reserve Component, the term "U.S. Naval Reserve" was superseded by "U.S. Navy Reserve" and the term USNR was discontinued as a matter of Total Force policy in 2005. All officers in the U.S. Navy now use the term USN with their rank titles.
Fully Warfare Qualified Unrestricted Line (URL) Officers[edit]
Unrestricted Line Officers (URL Officers) are commissioned Officers of the Line in the United States Navy who are qualified to Command at Sea the Navy's warfighting combatant units such as warships, submarines, aviation squadrons and SEAL Teams. They are also qualified to command the higher echelons of those units such as destroyer and submarine squadrons, aviation wings and groups, and special warfare groups. At the Flag Officer level, they also command carrier strike groups, expeditionary strike groups, task forces, and Fleet and Force commands. URL officers are also eligible to command shore installations, facilities and activities directly supporting the Navy's warfare mission.[2][3][4]
Previously qualified Naval Aviator or Naval Flight Officer whose operational flight rating has been terminated for medical or performance reasons, or by the individual's personal resignation.
131x
URL Officer qualified for duty involving piloting heavier-than-air, or heavier and lighter-than air types of aircraft as a Naval Aviator. Includes Naval Aviator-Astronaut.
132x
URL Officer qualified for duty involving flying heavier-than-air, or heavier and lighter-than-air type aircraft as a Naval Flight Officer. Includes Naval Flight Officer-Astronaut.
Non-Warfare Qualified Unrestricted Line (URL) Officers[edit]
110x General URL Officer without any warfare qualification (NOTE: the 110X designator is being phased out and superseded by various Restricted Line incumbents).
Training Designators For Unrestricted Line Officers[edit]
116x
URL Officer in training for Surface Warfare Officer qualification.
117x
URL Officer in training for Submarine Warfare Officer qualification.
118x
URL Officer in training for Special Warfare qualification.
119x
URL Officer in training for Special Operations qualification.
137x
URL Officer in training for duty involving flying as a Naval Flight Officer.
139x
URL Officer in training for duty involving flying as a Naval Aviator (pilot).
RL officers are authorized to command ashore within their particular speciality, but are not eligible for combatant command at sea, which remains strictly within the purview of URL officers.[4]
120x
RL Officer - Human Resources Officer.
121x
RL Officer - Nuclear Propulsion Training Officer (Nuclear Power School Instructor).
RL Officer - Information Warfare Officer (NOTE: Formerly designators 161x and 164x (Cryptology); merged and redesignated effective October 2010 under Information Dominance Corps).[5]
182x
RL Officer - Information Professional Officer (NOTE: Formerly designator 160x; redesignated effective October 2010 under Information Dominance Corps).[5]
183x
RL Officer - Intelligence Officer (NOTE: Formerly designator 163x, redesignated effective October 2010 under Information Dominance Corps).[5]