Assigned to patrol duty in Lingayen Gulf, Luzon, Pampanga operated in support of the Army engaged in fighting the Philippine–American War, carrying troops and supplies, providing shore bombardment to forces ashore, and blockaded rebel towns.

Pampanga was loaned to the Army for use as a patrol boat and ferry about Corregidor Island in Manila Bay on 31 December 1908 and was returned to the Navy on 11 November 1910.

On 24 September, the gunboat arrived off Semut, Basilan Island, and landed a detachment under Ensign Charles E. Hovey to take supplies to Army Camp Tabla inland.

En route, the small party was attacked by natives, killing Ensign Hovey and injuring three of his men.

In the course of her service, she cruised the West River to Canton and beyond protecting American interests, especially in the period of heavy unrest in the middle 1920s, and made frequent visits to Hong Kong, Swatow, and the other ports of the area in the performance of her duty.