These units were formed as part of the raising of the Third New Army, K3. They are also sometimes shown as 110, 111, 112 and 113 (Howitzer) Brigades RFA.
CX
- This brigade was originally comprised of A, B, C and D Batteries RFA and the Brigade Ammunition Column. It was placed under command of the 25th Division. The batteries were all armed with four 18-pounder field guns. The brigade then remained with the division throughout the war: you can see details of its battles and movements on the page describing the division.
- On 26 May 1916 the Brigade Ammunition Column left, being merged into the 25th Divisional Ammunition Column.
- On 31 May 1916 D Battery left, becoming the A Battery of 113 Brigade. The D (Howitzer) Battery of that brigade joined in its place.
- On 26-27 November 1916 the field gun batteries were made up to six guns each: C Battery was broken up and its two-gun sections joined A and B Batteries respectively; a new C Battery was formed from A and half of B Battery which arrived from 111 Brigade.
- D (Howitzer) Battery was also brought up to six howitzers by the arrival of a section of two from C (Howitzer) Battery of 113 Brigade on 14 January 1917.
- The brigade did not remain with the 25th Division when it was returned to England on 30 June 1918, but rejoined the reconstituted division on 4 October 1918 after it had arrived back in France.
CXI
- This brigade was originally comprised of A, B, C and D Batteries RFA and the Brigade Ammunition Column. It was placed under command of the 25th Division. The batteries were all armed with four 18-pounder field guns. The brigade then remained with the division throughout the war until it was broken up (see below): you can see details of its battles and movements on the page describing the division.
- On 26 May 1916 the Brigade Ammunition Column left, being merged into the 25th Divisional Ammunition Column.
- On 31 May 1916 D Battery left, becoming the B Battery of 113 Brigade. The D (Howitzer) Battery of that brigade joined in its place.
- On 27 November 1916 the brigade was broken up. A Battery and half of C went to 110 Brigade, becoming its new C Battery of six guns. B Battery and the other half of C Battery went to 112 Brigade. D (Howitzer) Battery went to 113 Brigade as its new C (Howitzer) Battery.
CXII
- This brigade was originally comprised of A, B, C and D Batteries RFA and the Brigade Ammunition Column. It was placed under command of the 25th Division. The batteries were all armed with four 18-pounder field guns. The brigade then remained with the division throughout the war: you can see details of its battles and movements on the page describing the division.
- On 26 May 1916 the Brigade Ammunition Column left, being merged into the 25th Divisional Ammunition Column.
- On 31 May 1916 D Battery left, becoming the C Battery of 113 Brigade. The D (Howitzer) Battery of that brigade joined in its place.
- On 26-27 November 1916 the field gun batteries were made up to six guns each: B Battery and a section of C Battery joined from111 Brigade were split up for this purpose.
- D (Howitzer) Battery was also brought up to six howitzers by the arrival of a section of two from C (Howitzer) Battery of 113 Brigade on 14 January 1917.
- The brigade did not remain with the 25th Division when it was returned to England on 30 June 1918, but rejoined the reconstituted division on 4 October 1918 after it had arrived back in France.
CXIII (Howitzer)
- This brigade was originally comprised of A, B, C and D (Howitzer) Batteries RFA and the Brigade Ammunition Column. It was placed under command of the 25th Division. The batteries were all armed with four 4.5-inch howitzers. The brigade then remained with the division throughout the war until 14 February 1917: you can see details of its battles and movements on the page describing the division.
- On 15 December 1915 B (Howitzer) Battery left to join 131 Brigade, then with 2nd Canadian Division.
- On 26 May 1916 the Brigade Ammunition Column left, being merged into the 25th Divisional Ammunition Column.
- On 31 May 1916 the brigade was reorganised. A, C and D (Howitzer) Batteries all left and became the D (Howitzer) Batteries of 110,111 and 112 Brigades respectively. They were replaced by the D Batteries (field gun units) from those brigades.
- On 26-27 November 1916 the field gun batteries were made up to six guns each: C Battery was broken up and its two-gun sections went to A and B Batteries. Next day D (Howitzer) Battery joined from 111 Brigade and became C (Howitzer) Battery.
- On 5 December 1916 507 (Howitzer) Battery joined from 7th Division and became D (Howitzer) Battery.
- The brigade left 25th Division to become an Army Brigade on 14 February 1917. C (Howitzer) Battery was then broken up to bring the D (Howitzer) Batteries of 110 and 112 Brigades up to six howitzers each.
- On 22 February 1917 B Battery (field guns) of 172 Brigade of 36th (Ulster) Division and became a new C Battery. A section of two joined from C (Howitzer) Battery of 172 Brigade and was used to bring D (Howitzer) Battery up to six howitzers.