The 24-year-old, who saved three penalties in United's play-off shootout victories over Alfreton Town and Scunthorpe United in April, will be wearing the number one jersey for the club when the National League campaign kicks off on Saturday August 10.
Gregory, a January 2023 signing from Kettering Town, has been a revelation for the Pilgrims and provides an eye-catching start to Ian Culverhouse's retention process.
Further re-signings - and announcements - are in the offing as United gear up for their first season as a Step 1 club since 2002.
Supporters are reminded, meanwhile, that season tickets for the National League season are on sale here - at early bird rates until Friday May 31.
PIC: Lee Keuneke.