William Hart was commissioned on September 26, 2019, by Rear Adm. Kevin Lunday after arriving in Honolulu after a 140-day pre-commissioning deployment from Key West, Florida. A celebration was held on September 26, 2019, to celebrate the commissioning.
In 2020, she participated in Operation Kuru Kuru for 36 days to deter Illegal, unreported and unregulated fishing (IUU) around American Samoa. This would be the first unsupported FRC patrol in Exclusive Economic Zones (EEZs), with her patrolling four EEZs in Oceania.
In June 2021, she completed her first Command Assessment of Readiness for Training and Tailored Ship's Training Availability with a 96% score.
In September 2021, she took part in the rescue of a 67-year-old man from the S/V Epic after it was lost at sea for nine days.
Between October and November 2021, she completed a second unsupported IUU patrol in Oceania for another 36 days.
Between January and February 2023, she partook in Operation Aiga, which was another 42-day IUU patrol.[2]
She is named for William C. Hart, a sailor of the Coast Guard who earned the Gold Lifesaving Medal when he jumped off CG-213, which he was commanding, to save a member from the Thomas Tracy who had fallen overboard during a storm.[3]