After post-shakedown repairs, Sigourney sailed, on 14 September 1943, from Norfolk with cruiser Baltimore (CA-68) en route to the west coast.

On the night of 29 February–1 March, Sigourney, with DesRon 22, engaged in an antishipping sweep of Simpson Harbor and then bombarded Rabaul and the airfield on Duke of York Island in the Bismarck Archipelago.

During March, Sigourney and her destroyer division operated under the direction of the Commanding General, U.S. XVI Corps, in support of forces on Bougainville.

Sigourney engaged in daily bombardments in the Jaba River and Motapena Point area and supported PT boat operations at night.

Sigourney then made escort trips between Guadalcanal, Cape Gloucester, Purvis Bay, Majuro, Eniwetok and Kwajalein.

On 11 May, the destroyer sortied from Kwajalein with Task Group 51.18 (TG 51.18), the Joint Expeditionary Force, Reserve, for the amphibious assault on Saipan and Tinian in the Mariana Islands.

During her time on station, she bombarded beaches on both islands, supplied call-fire support for the forces ashore, and served as a picket ship and as an antisubmarine screen.

On 19 October 1944, Sigourney shelled Red and White Beaches to cover underwater demolition teams reconnoitering the landing sites near Dulag and Tacloban.

She and Cony (DD-508) remained in the area while the remainder of TG 77.2 withdrew to the south to cover the approaches to Leyte Gulf through Surigao Strait.

On the 20th, they bombarded the beaches until H-hour and then provided call-fire support until the 24th when word was received from the Commander, 7th Fleet, to prepare for a night engagement.

Sigourney, Aulick (DD-569), and Welles (DD-628) were in the van as Attack Section 2 of DesDiv "X-Ray" which would screen the battle line consisting of six battleships.

She moved to San Diego the next day and, a month later was underway, for New York City via the Panama Canal, arriving there on 20 October.

Sigourney was placed in full commission again on 7 September 1951 at Charleston, S.C. She underwent shakedown training at Guantanamo Bay in early 1952 and, in April, joined DesRon 322 with Norfolk as her home port.

On 10 December 1953, Sigourney began her goodwill cruise which took her to Hong Kong, Singapore, Naples, Cannes, Gibraltar, and Lisbon before returning to Norfolk on 6 February 1954.

The Sigourney appeared in the movie Away All Boats, accurately depicting the Fletcher destroyer class's anti-aircraft role in the Pacific Theater.