Royce, whose performances between the sticks saved the Gills on countless occasions last season, was kept waiting for a number of weeks after shaking hands on a deal before the end of the season.
But that uncertainty has now been erased with the confirmation that Royce has signed for next season - and the former Leicester and Charlton custodian said he was delighted to finally sign on the dotted line for Gillingham.
Royce told the Kent Messenger: "I'm pleased to sign and I've signed for Mark Stimson really. If it was anyone else I might not have signed, and I could have gone somewhere else.
"He's staying and I get on really well with him so that's the main reason I signed.
"The other reason is the fans. I want to thank them for everything they've done for me and the way they've really made me feel welcome at the club.
"I would have gone somewhere else and I would have had no problem getting another club. I spoke to a Championship club and was waiting to see what they were doing - there would have been something else too."
Gills manager Mark Stimson was also happy to see Royce's future with the club confirmed, saying: "He's going to be a vital player for us next season and one that we will need to help get this club back to where we want to be."