After returning to Pearl Harbor 10 August, Lamar held landing rehearsals off Maui Island to prepare for the invasion of the Philippines.

While debarking assault troops and unloading cargo at Dulag under cover of smoke, she fought off enemy air attacks, and on the 21st splashed a Japanese bomber.

Sailing 31 December with task group TG 79.1, she entered Lingayen Gulf 9 January 1945 and began debarking combat troops.

Despite frequent alerts and intermittent air attacks, the transport completed unloading the 11th and departed for Leyte, where she arrived 14 January.

Assigned to task group TG 55.1, she reached Okinawa 1 April and completed landing men and cargo the next day.

Departing San Francisco 22 May, Lamar deployed passengers and cargo to Pearl Harbor and Ulithi before reaching Guiuan, Samar, 23 June.