3 West Connemara – 4 Western Division

1 Battalion: Unit strength on 11 July 1921 was 367 all ranks, and the strength on 1 July 1922 was 388 all ranks.The companies of the 1 Battalion were located as follows:  Leenane, Cornamone,  Cloughbrack, Finny, Lettergesk and Kilmilken.
2 Battalion: Unit strength on 11 July 1921 was 564 all ranks. This unit in the formation given below did not exist on the second critical date. On 11 July 1921 the companies of the 2 Battalion were located as follows:  Rossmuck,  Carraroe,  Lettermore,  Tiernea,  Ballinakill,  Lettermullen,  Clynagh,  Camus and Kilkerrin. By 1 July 1922 eight of the companies of this battalion had been posted to the 2 Battalion, 4 Brigade and one company to the 3 Battalion, 3 Brigade of the 4 Western Division. The following companies had been posted to the 2 Battalion, 4 Brigade: Rossmuck, Carraroe,  Lettermore,  Tiernea,  Ballinakill,  Lettermullen,  Clynagh, and Camus;  and the Kilkerrin company had been posted to the 3 Battalion, 3 Brigade.
2 Battalion (Louisburg): Unit strength on 1 July 1922 was 545 all ranks. This unit in the formation given below did not exist on the first critical date.On 1 July 1922 the companies of the 2 Battalion (Louisburg) were located as follows:  Louisburg, Killeen, Achony, Lecanvey, Cullen, Tully, Cregganbaun and Drummin.
3 Battalion (Roundstone): Unit strength on 11 July 1921 was 367 all ranks, and the strength on 1 July 1922 was 435 all ranks.The companies of the 3 Battalion were located as follows: Roundstone,  Carna,  Cashel,  Recess and Calla.  By 1 July 1922 The Kilkerrin Company was posted to the 3 Battalion (Roundstone)  from the 2 Battalion. (See above).
4 Battalion (Clifden): Unit strength on 11 July 1921 was 314 all ranks, and the strength on 1 July 1922 was 302 all ranks.The companies of the 4 Battalion were located as follows:  Clifden,  Cleggan,  Ballinakill,  Boffin Island,  Tullycross and Letterfrack.

An Active Service Unit with a strength of 47 members was in effect on 11 July 1921. Personnel were attached to the A.S.U. from the battalions of the brigade. There is no data provided for the second critical date of 1 July 1922.