"Swordfish" completed fitting out and held her shakedown in the Atlantic Ocean. After post-shakedown availability and subsequent sea trials along the East Coast, she was assigned a home port at Pearl Harbor, Territory of Hawaii, effective 16 March 1959. She steamed to Hawaii in July and was the second nuclear-powered submarine to join the United States Pacific Fleet, joining . Assigned to Submarine Squadron 1, "Swordfish" steamed over 35,000 miles during her first year in commission with over 80% of them submerged.