The 21-year-old, who made 14 appearances on loan at London Road last season, has signed a four-year contract with the club.
"Some good news non striker related. Pleased to announce Jack Payne has signed a 4 yr deal with us. Quality acquisition Poshies," MacAnthony tweeted.
"I'm pleased we as a club continue to purchase top quality young league talent which in turn sees FL clubs benefit financially.
"Jack P will only enhance our already strong squad as we work towards competing for league 1 honours."
Payne made his debut for Gillingham in October 2008.