After commissioning, "Geelong" visited her namesake city before undergoing working up trials. On completion, the corvette was assigned as a minesweeper and anti-submarine patrol ship along the east coast of Australia, before being redeployed to New Caledonia on 8 March 1942 to perform similar duties. In May 1942, "Geelong" returned Sydney, and was one of several Allied vessels located in Sydney Harbour during the Japanese midget submarine attack of 31 May 1942. In June, the ship began convoy escort runs between Sydney and Brisbane, which continued until January 1944, when she sailed to Adelaide for a two-month refit.