Defender Matt Lawrence, midfielders Danny Spiller, Curtis Weston and Dean Rance as well as forward Dennis Oli have all not been offered new deals.
The quintet are among several players whose terms expire this summer but decisions on the remainder have been deferred until a later date following the departure of manager Andy Hessenthaler on Tuesday.
Hessenthaler, in his second spell in charge of the Kent club, stepped down having been unable to secure a play-off berth.
He has, however, been offered a place on the board and a football development role at the club where he also spent 10 years as a player.
