[8] The 2023 reform amalgamated Addington and Tide Head with Campbellton, annexing Glencoe with two parts of the LSD of the parish of Addington on either side of Walker Road, allowing a smoother boundary, while the boundary between the river islands was settled;[5] Flatlands and the remainder of the parish LSD became part of the rural district.

[6] The parish was named in honour of Henry Unwin Addington, a diplomat who was appointed in 1826 as a plenipotentiary in the boundary negotiations with the United States.

[11] The parish comprised the area north of the prolongation of the southern line of modern Beresford and between the Benjamin and Upsalquitch Rivers.

[15][16][17][18][19] Parish population total does not include Tide Head or portions in Atholville and Campbellton.

Revised census figures based on the 2023 local governance reforms have not been released.