3 Brigade Donegal – 1 Northern Division

1 Battalion: Unit strength on 11 July 1921 was 195 all ranks, and the strength on 1 July 1922 was 372 all ranks. The companies of the 1 Battalion were located as follows: Frosses, Drimarone, Mountcharles, Killaghter and Inver.
2 Battalion: Unit strength on 11 July 1921 was 312 all ranks, and the strength on 1 July 1922 was 352 all ranks. The companies of the 2 Battalion were located as follows: Killybegs, Kilcar, Carrick, Glencolumcille and Meeninarry.
3 Battalion: Unit strength on 11 July 1921 was 197 all ranks, and the strength on 1 July 1922 was 298 all ranks. The companies of the 3 Battalion were located as follows: Ardara, Rosbeg, Kilclooney, Doobin and Edinfinfreagh.
4 Battalion: Unit strength on 11 July 1921 was 233 all ranks, and the strength on 1 July 1922 was 314 all ranks. The companies of the 4 Battalion were located as follows: Maas & Glenties, Derryloughan, Glenties, Fintown and Letterbrick.