13th Combat Service Support Battalion (13 CSSB) is a unit of the 13th Brigade of the Australian Army Reserve.

Located in Western Australia, it is the logistics component of the 13th Brigade.

On formation, it consisted of the following sub-units:[1] 13 CSSB was granted "Freedom of Entry" to the City of Fremantle on 1 October 2001.

[1] The role of 13 CSSB is to provide service and logistics support to the 13th Brigade and wider Australian Army.

A Reserve unit, it is based at Irwin Barracks,[1] and as of February 2020, 13 CSSB comprises a battalion headquarters and four sub-units:[citation needed]