Captain Barry Fuller and defender Gary Richards are already considering offers from new manager Andy Hessenthaler.
Eight out-of-contract players have been released from Priestfield Stadium with Adam Miller the highest profile of those to go.
He made 97 appearances for the Gills in two-and-a-half years with the club and scored 13 goals.
Defender Tom Wynter, midfielders Rashid Yussuff and Stewart Lewis, and strikers Luis Cumbers, Andy Pugh, Jacob Erskine and James Walker have also been released.
No decision has yet been made on goalkeeper Simon Royce or midfielder Mark Bentley.
Source: BBC Sport
Source: BBC Sport