December 12 till December 29, 1944
The battalion commenced its first operation in the Doiabi River and Sisivie area.
December 29 till December 31, 1944
The battalion prepares for the first campaign in the Numa Numa area.
December 31, 1944 till January 4, 1945
The 26th Battalion relieved the 25th Battalion in the Piaterapaia area.
January 5 till February 2, 1945
The first patrols moved out into hostile territory making enemy contact on January 6. The unit was operating in the Numa Numa area. The unit's operations covered Pearl Ridge, Vivie, Keenans Ridge, Smith's Hill and Chamber's Hill areas. On January 31 the battalion was relieved by the 55th/53rd Battalion and moved back to Torokina.
February 2 till February 21, 1945
Resting at Torokina. On February, 7, Col Abbott relinquished command of the battalion and Lt-Col B.J. Callinan MC MID assumed command of the unit.
February 21 till April 4, 1945
The battalion carried out its second campaign in the Soraken Plantation area. On March 28, Col Callinan advised the 11th Bde that all organised resistance had ceased in the Soraken. The unit moved to 'I' Beach having been relieved by the 55th/53rd Battalion.
April 4 till May 19, 1945
The battalion commenced its third campaign in the Ratsua-Ruri Bay area after relieving the 55th/53rd Battalion.
May 19 till June 28, 1945
The unit worked in close conjunction with the 31st/51st Battalion during this campaign. From time to time companies were detached to each other's unit to strengthen the forces required to dislodge the enemy. The 26th Battalion was relieved by the 27th Battalion and moved back to Torokina.
June 28 till September 25, 1945
The unit was based at Torokina for resting and refurbishment of men and equipment. On September 25 the 26th Battalion departed Torokina and arrived at Rabaul for garrison duty. The unit was completely reorganised, many men were discharged and then reinforced by men from units which had been made redundant.