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Part III, Subpart ii, Chapter 2, Section HService Department Organizational Structures and Service Number Assignments

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Contents21 blocks

Revised December 13, 2005

III.ii.2.H.1.aArmy Echelons and Appropriate Designations

The table below lists the Army echelons and appropriate designations.

EchelonsDesignations
Army

Numerical/Geographical

Corps

Roman numeral

Division

Numerical by combat arm

Brigade

Numerical or combat command, such as Alpha

Regiment

Numerical by combat arm

Group

Numerical by combat arm

Battalion

Numerical/battle group numerical/squadron numerical

Company

Alpha/Battery - Alpha/Troop - Alpha

Platoon

Numerical/Detachment – Numerical

Squad

Numerical

Fire Team

---

III.ii.2.H.1.bAvailability of Organizational Records

Rosters, morning reports, and sick reports may be available down to the company level. Note: The Army discontinued morning reports in 1974/1975.

III.ii.2.H.1.cOther Organizational Units that May Have Created Records

Records, including clinical and medical records, may exist for other organizations and units, such as

  • garrison-type units, and
  • hospitals.

Important: If a unit was considered independent from higher echelons, it may have created its own records.

2Navy Organizational Structure

This topic contains information on the Navy organizational structure, including

  • Navy echelons and appropriate designations
  • echelons for the
    • Naval Air Force
    • Naval Surface Force, and
    • Naval Submarine Force
  • ship designations, and
  • shore establishment organization.

Revised August 13, 2009

III.ii.2.H.2.aNavy Echelon and Appropriate Designations

The table below lists the Navy echelon and appropriate designations. For clarification, samples of unit designations are shown in italics.

EchelonDesignations

Fleet-Atlantic Pacific

Numbered fleets

Fleet

Numerical (7 th Fleet; 7thFlt.)

Task force

Task force number and type of force (CTF-45 Battle Force) Notes:

  • Task forces are operational sub-units of fleets organized to perform specific missions for the fleet.
  • The following are Naval Task forces:
    • the Naval Air Force
    • the Naval Surface Force, and
    • the Naval Submarine Force.

Fleet Marine Force

Reference: For more information on the Fleet Marine Force, see M21-1, Part III, Subpart ii, 2.H.4.

U.S. Naval Forces Europe

---

Middle East Force-Persian Gulf

---

III.ii.2.H.2.bEchelon for the Naval Air Force

The following list shows the echelon for the Naval Air Force:

  • carrier strike group (CSG 5)
  • carrier air wing, and (CVW-2)
  • squadron (VFA-2; VAQ-131)

Notes:

  • Carrier strike groups were historically designated carrier battle groups.
  • Carrier air wings were historically designated carrier air groups.

III.ii.2.H.2.cEchelon for the Naval Surface Force

The following list shows the echelon for the Naval Surface Force:

  • flagship, and
  • Cruiser Destroyer Group Squadron (CCDG-5; DESRON-23)

Note: The Cruiser Destroyer Group Squadron consists of the Surface Group, Service Group Squadron, Amphibious Group Squadron, Mine Group Division, and Special Warfare Group.

III.ii.2.H.2.dEchelon for the Naval Submarine Force

The following list shows the echelon for the Naval Submarine Force:

  • submarine group, and
  • submarine squadron (SUBRON 11)

III.ii.2.H.2.eShip Designations

Individual ships under the above echelons are identified as USS (name of ship) followed by an alpha-numerical hull number which

  • distinguishes the ship from other ships with the same name that may have preceded or may have followed it, and
  • identifies the type of ship.

Example: USS Independence CVA-62.

III.ii.2.H.2.fShore Establishment Organization

Shore establishments, such as non-moveable shore installations, were organized as bureaus (technical in nature) that, with the exception of personnel and medicine and surgery, became the Naval material command in 1963. Other system type commands have followed this tradition.

3Air Force Organizational Structure

This topic contains information on the Air Force organizational structure, including

  • Air Force echelons and appropriate designations
  • availability of organizational records, and
  • other organizational units that may have created records.

Revised December 13, 2005

III.ii.2.H.3.aAir Force Echelon and Appropriate Designations

The table below lists the echelon of Air Force units and appropriate designations.

UnitsDesignations
Command

Geographical/specified mission

Air force

Numerical/geographical

Air Division

Numerical

Wing

Numerical/specified mission

Group

Numerical/specified mission

Squadron

Numerical/specified mission/alpha

Flight

Numerical—Alpha

III.ii.2.H.3.bAvailability of Organizational Records

Other organizational records may be available, such as

  • medical records
  • rosters
  • morning reports
  • courts martial, and
  • academic records.

Notes:

  • Some records may have a limited retention period.
  • Academic records dated after 1967 may be obtained from another National Archives and Records Administration center, if still retained.
  • Morning reports were discontinued in June 1966.

III.ii.2.H.3.cOther Organizational Units That May Have Created Records

Records, including clinical and medical records, may exist for other organizations and units, such as

  • agency center
  • hospital
  • office
  • service, and
  • academy.

4Marine Corps Organizational Structure

This topic contains information on the Marine Corps organizational structure, including

  • Marine Corps echelons and appropriate designations
  • division echelons, and
  • availability of organizational records.

Revised January 5, 2017

III.ii.2.H.4.aMarine Corps Echelons and Appropriate Designations

The table below lists the Marine Corps echelons and appropriate designations. For clarification, samples of unit designations are shown in italics.

EchelonDesignation

Fleet Marine Force

Atlantic/Pacific (FMFPac)

Marine Amphibious Force Note: Consists of the

  • Marine Division
  • Marine Aircraft Wing, and
  • Marine Logistics Group
    • historically, Force Service Support Group, and
    • counterpart, Marine Wing Support Group.

Roman numeral (I MAF) (operational)

Division Note: Major sub-elements consist of

  • regiments, and
  • battalions.

Numerical (3rdMarDiv) Reference: For more information on the echelons of a division, see M21-1, Part III, Subpart ii, 2.H.4.b.

Wing Note: Major sub-elements consist of

  • groups, and
  • squadrons.

Numerical (1stMAW) Note: Squadrons are designated alpha-numerically. (VMA-211; HMM-262)

Marine Expeditionary Force (MEF) Note: Marine Air ground task force for operations and exercises which consists of the

  • Marine Division
  • Marine Aircraft Wing, and
  • Marine Logistics Group.

Roman numeral (III MEF)

Marine Expeditionary Brigade (MEB) Note: Marine Air ground task force for operations and exercises which consists of the

  • Regimental Landing Team
  • Composite Aircraft Group, and
  • Combat Logistics Regiment.

Numerical (3d MEB)

Marine Expeditionary Unit (MEU) Note: Marine Air ground task force for operations and exercises which consists of the

  • Battalion Landing Team
  • Composite Aircraft Squadron, and
  • Combat Logistics Battalion

Numerical (31 MEU)

Notes:

  • Expeditionary units replaced historically designated amphibious units.

  • Logistics units replaced historically designated force service support units.

III.ii.2.H.4.bDivision Echelons

The table below lists the Marine Corps division echelons and appropriate designations.

EchelonDesignation
Regiment

Numerical (7 th Marines; 7th Mar.)

Battalion

Numerical (2 nd Battalion; 2nd Bn)

Company

Alpha or phonetic (D Company; Delta Co.)

Platoon

Numerical (1 st Platoon; 1st Plt.)

Squad

Numerical (3 rd Squad; 3rd Sqd.)

III.ii.2.H.4.cAvailability of Organizational Records

The organizational records listed below are available for the years shown.

  • Muster rolls are available for the years 1801 through present.
  • Indexes are available for the years 1897 through 1939.
  • Unit diaries are available for the years 1949 through 1964.
  • Bound diaries are available back to 1901.

Notes:

  • Unit diaries have been microfilmed and are stored on the 5th floor of the National Personnel Records Center (NPRC). These unit records may include
    • command chronologies
    • operational situation reports (sitreps), and
    • operation after-action reports.
  • Some individual reels may be unusable due to poor storage conditions.
  • Marine Corps headquarters maintains duplicate copies of the unit diaries.
  • Many Marine Corps unit records are stored on compact discs (CDs) and accessed via the Stressor Verification page.

Reference: For more information on accessing these records, see

5Guide for Service Numbers 1 through 9,999,999

This topic contains a guide to service numbers 1 through 9,999,999, including

  • Army service numbers
  • Navy service numbers
  • Marine Corps service numbers, and
  • Coast Guard service numbers.

Revised July 23, 2018

III.ii.2.H.5.aArmy Service Numbers

The table below lists the numbers used for Army enlisted personnel for the periods shown. Notes:

  • The Army originally assigned Air Force service numbers lower than 10,000,000.
  • Omitted blocks of numbers were not assigned.
SeriesDates Assigned

1 through 5,999,999

1918 through 1919

6,000,000 through 7,999,999

1919 through 1940

8,000,000 through 8,999,999

1948 and after (for Women only)

III.ii.2.H.5.bNavy Service Numbers

The table below lists the numbers used for Navy enlisted personnel for the periods shown.

SeriesDates Assigned

1,000,000 through 1,999,999

1885-1918

2,000,000 through 9,999,999

1918-1965

100,000 and higher (Letter Prefix)

1965 and after

III.ii.2.H.5.cMarine Corps Service Numbers

The table below lists the numbers used for Marine Corps enlisted personnel for the periods shown.

SeriesDates Assigned

20,000 through 99,999

1905 through 1917

100,000 through 349,999

1917 through 1941

350,000 through 670,899

1941 through 1947

700,000 through 799,999

reserved for female enlisted personnel only

800,000 through 999,999

1943 through 1947

1,000,000 through 1,699,999

1944 through 1957

1,700,000 through 1,799,999

reserved for female enlisted personnel only

1,800,000 through 1,999,999

1956 through 1965

2,000,000 and higher

1964 and after

III.ii.2.H.5.dCoast Guard Service Numbers

The table below lists the numbers used for Coast Guard enlisted personnel for the periods shown.

SeriesDates Assigned

100,000 through 199,999

through 1930

200,000 through 254,999

1930 through 1942

255,000 through 349,999

1945 through 1962

350,000 through 499,999

1962 until 1974

500,000 through 999,999

1941 through 1945

2,000,000 through 2,199,999

1948 through 1974

6Guide for Service Numbers 10,000,000 through 19,999,999

Revised December 13, 2005

III.ii.2.H.6.aRegular Army and Regular Air Force Enlisted Service Numbers

The table below lists the numbers used for regular Army and regular Air Force enlisted personnel for the periods shown. Notes:

  • Series 10,000,000 through 10,999,999 are used for initial enlistments occurring outside the continental limits.
  • The Army originally assigned Air Force service numbers lower than 10,000,000.
SeriesDates Assigned

10,000,000 through 10,999,999

1940 and after

11,000,000 through 11,142,500

1940 through 1945

11,142,501 through 11,188,000

1946 through 1948

11,188,001 through 11,238,500

1949 through 1951

11,238,501 through 11,283,000

1952 through 1954

11,283,001 through 11,344,500

1955 through 1957

11,344,501 through 11,384,000

1958 through 1960

11,384,001 through 11,999,999

1961 and after

12,000,000 through 12,242,000

1940 through 1945

12,242,001 through 12,321,000

1946 through 1948

12,321,001 through 12,393,500

1949 through 1951

12,393,501 through 12,469,000

1952 through 1954

12,469,001 through 12,553,375

1955 through 1957

12,553,376 through 12,614,900

1958 through 1960

12,614,901 through 12,999,999

1961 and after

13,000,000 through 13,197,500

1940 through 1945

13,197,501 through 13,299,700

1946 through 1948

13,299,701 through 13,408,700

1949 through 1951

13,408,701 through 13,511,500

1952 through 1954

13,511,501 through 13,621,140

1955 through 1957

13,621,141 through 13,705,500

1958 through 1960

13,705,501 through 13,999,999

1961 and after

14,000,000 through 14,204,500

1940 through 1945

14,204,501 through 14,300,770

1946 through 1948

14,300,771 through 14,454,000

1949 through 1951

14,454,001 through 14,547,500

1952 through 1954

14,547,501 through 14,661,000

1955 through 1957

14,661,001 through 14,745,000

1958 through 1960

14,745,001 through 14,999,999

1961 and after

15,000,000 through 15,201,000

1940 through 1945

15,201,001 through 15,280,500

1946 through 1948

15,280,501 through 15,465,760

1949 through 1951

15,465,761 through 15,530,600

1952 through 1954

15,530,601 through 15,593,615

1955 through 1957

15,593,616 through 15,639,615

1958 through 1960

15,639,616 through 15,999,999

1961 and after

16,000,000 through 16,201,500

1940 through 1945

16,201,501 through 16,307,000

1946 through 1948

16,307,001 through 16,398,890

1949 through 1951

16,398,891 through 16,481,925

1952 through 1954

16,481,926 through 16,600,497

1955 through 1957

16,600,498 through 16,638,100

1958 through 1960

16,683,101 through 16,999,999

1961 and after

17,000,000 through 17,183,500

1940 through 1945

17,183,501 through 17,254,500

1946 through 1948

17,254,501 through 17,338,810

1949 through 1951

17,338,841 through 17,410,300

1952 through 1954

17,410,301 through 17,512,785

1955 through 1957

17,512,786 through 17,592,940

1958 through 1960

17,592,941 through 17,999,999

1961 and after

18,000,000 through 18,247,100

1940 through 1945

18,247,101 through 18,360,800

1946

18,360,801 through 18,546,000

1947 through 1957

18,546,001 through 18,607,725

1958 through 1960

18,607,726 through 18,999,999

1961 and after

19,000,000 through 19,235,500

1940 through 1945

19,235,501 through 19,324,485

1946 through 1948

19,324,486 through 19,420,000

1949 through 1951

19,420,001 through 19,520,770

1952 through 1954

19,520,771 through 19,590,665

1955 through 1957

19,590,666 through 19,597,661

1958

19,597,662 through 19,999,999

1959 and after

7Guide for Service Numbers 20,000,000 and Higher

Revised December 13, 2005

III.ii.2.H.7.aService Numbers 20,000,000 and Higher

The table below lists the service numbers 20,000,000 and higher, the time periods in which they were issued, and the service categories to which they were issued.

SeriesPeriod IssuedService Category

20,000,000 through 20,999,999

1940 through 1946

Enlisted National Guard in active duty.

21,000,000 through 29,999,999

1946 and after

Enlisted National Guard of the U.S.

30,000,000 through 39,999,999

1940 through 1946

Enlisted personnel inducted into the Army of the U.S.

40,000,000 through 41,999,999

---

Apparently not used or allocated.

42,000,000 through 46,999,999

1943 through 1946

Enlisted personnel inducted into the Army of the U.S.

47,000,000 through 49,999,999

---

Apparently not used or allocated.

50,000,000 through 59,999,999

1948 through 1966

Army and Air Force Emergency Interim Issue (EM). Note: Regular Army and Air Force are not included.

60,000,000 through 69,999,999

1966 and after

Army and Air Force EM. Note: Regular Army and Air Force are not included.

70,000,000 through 89,999,999

---

Apparently not used or allocated.

90,000,000 through 99,999,999

1940 through 1945

Only a limited number, about 20,000 within this series, were used for the Philippine Army during World War II. Note: There is no evidence of other usage.

End of Part III, Subpart ii, Chapter 2, Section H

This text is a rendering of Part III, Subpart ii, Chapter 2, Section H. The official version is the one that governs your claim.

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