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British naturalisation certificate prefix codes 1844-1990

Naturalisation certificate prefix codes

This table explains the codes prefixed to British naturalisation certificate numbers.

naturalisation act

year range

certificate prefix code

certificate type

Naturalisation Act, 1870

1870-1914

A

Certificate (ordinary) to a person with five years residence in the U.K. during the eight years immediately preceding application for Naturalisation

Naturalisation Act, 1870

1870-1914

AA

Certificate to person with five years service under the Crown during the eight years immediately preceding application for Naturalisation

Naturalisation Act, 1870

1870-1914

AAA

Certificate to person in the Diplomatic or Consular Service with five years service under the Crown during the eight years immediately preceding application for Naturalisation

Naturalisation Act, 1870

1870-1914

B

Certificate to person who has already been granted a Certificate of Naturalisation under the earlier Act of 1844

Naturalisation Act, 1870

1870-1914

C

Certificate to a person of Doubtful Nationality with five years residence in the U.K., or five years service under the Crown, during the eight years immediately preceding application for re-admission

Naturalisation Act, 1870

1870-1914

D

Certificate of re-admission of person to British Nationality with five years residence in the U.K., or five years service under the Crown, during the last eight years immediately preceding application for re-admission

Naturalisation Act, 1870

1870-1914

E

Declaration made by a person, a subject of a foreign state subsequently naturalised as a British subject, renouncing British nationality

Naturalisation Act, 1870

1870-1914

F

Declaration by a person, an alien by origin but born within H.M. dominions, renouncing British nationality

Naturalisation Act, 1870

1870-1914

G

Declaration by a person, born out of H.M. dominions of a father being a British subject, renouncing British nationality

Naturalisation Act, 1870

1870-1914

H

Declaration by a natural-born British subject, renouncing subsequent Naturalisation in a foreign state

British Nationality and Status of Aliens Act, 1914

1915-1949

A and AZ

Certificate (ordinary) granted under Section 2 of the Act, where the names of children are not included

British Nationality and Status of Aliens Act, 1914

1915-1949

B and BZ

Certificate (ordinary) granted under Section 2 of the Act, with the names of children included

British Nationality and Status of Aliens Act, 1914

1915-1949

C and CZ

Certificate granted under sub-section (2) of Section 5 of the Act to a minor

British Nationality and Status of Aliens Act, 1914

1915-1949

D

Special certificate granted under Section 4 of the Act to a person with respect to whose nationality a doubt exists, where the names of children are not included

British Nationality and Status of Aliens Act, 1914

1915-1949

DZ

Certificate of Naturalisation granted to a woman who was at birth a British subject and is married to a subject of a state of war with His Majesty

British Nationality and Status of Aliens Act, 1914

1915-1949

E

Special certificate granted under Section 4 of the Act to a person with respect to whose nationality a doubt exists, with the names of children included

British Nationality and Status of Aliens Act, 1914

1915-1949

EZ

Certificate of Naturalisation granted to a woman who was at birth a British subject and is married to a subject of a state of war with His Majesty, with names of children included

British Nationality and Status of Aliens Act, 1914

1915-1949

F

Certificate granted under Section 6 of the Act to a person naturalised before the passing of the Act, where the names of children are not included

British Nationality and Status of Aliens Act, 1914

1915-1949

FZ

Certificate of Naturalisation granted to a French national where the names of children are not included

British Nationality and Status of Aliens Act, 1914

1915-1949

G

Certificate granted under Section 6 of the Act to a person naturalised before the passing of the Act, with names of children included

British Nationality and Status of Aliens Act, 1914

1915-1949

GZ

Certificate of Naturalisation granted to a French national with names of children included

British Nationality and Status of Aliens Act, 1914

1915-1949

M

Special Certificate granted under Section 4 of the Act to a person with respect to whose nationality a doubt exists

British Nationality and Status of Aliens Act, 1914

1915-1949

O

Certificate granted under Section 8 of the Act by the Government of a British Possessions overseas

British Nationality Act, 1948

1949-1990

BNA

Application made by a subject of a foreign state resident in the U.K.

British Nationality Act, 1948

1949-1990

M

Application for registration of a minor child, under s7 & 18 1948 Act

British Nationality Act, 1948

1949-1990

O

Application made by a subject of a foreign state resident overseas

British Nationality Act, 1948

1949-1990

R1

Application made by an adult British subject or citizen of the Republic of Ireland, or any of the Channel Islands, Isle of Man, a colony, a protectorate or a protected state to which s8(1) of the Act applied, or a U.K. Trust Territory, or on the grounds of Crown Service under H.M. Government in the U.K., under s6(1) 1948 Act

British Nationality Act, 1948

1949-1990

R2

Application made by a woman who has been married to a citizen of the U.K. and colonies, under s6 (2) 1948 Act

British Nationality Act, 1948

1949-1990

R3

Application made by a foreign woman who has been married to a citizen of the U.K. and colonies, under s6 (2) 1948 Act

British Nationality Act, 1948

1949-1990

R4

Application made by a person who but for his citizenship or potential citizenship of one of the countries mentioned in s1 (3) of the Act would have become a citizen of the U.K. and colonies under s12 (4) of the Act, under s12 (6) 1948 Act

British Nationality Act, 1948

1949-1990

R5

Application to resume British nationality by a person who has ceased to be a British subject on the loss of British nationality by his father or mother in accordance with s12 (1) of the 1914 Act, under s16 1948 Act

British Nationality Act, 1948

1949-1990

R6

Declaration of renunciation of citizenship made by a citizen of the U.K. and colonies who is also a citizen of one of the countries mentioned in s13 of the Act or of the Republic of Ireland or a national of a foreign country, under s19 1948 Act