Peter Clarke, Simon Francis and Nicky Bailey have all been placed on Southend's transfer list as manager Steve Tilson sets about reshaping his squad.
All three players are first team regulars at Roots Hall but having rejected new deals, they have been informed by Tilson that they have been made available for transfer.
Clarke and Francis have 12 months on their contracts left while Bailey has another two years left to run and they join Matt Harrold, Charlie MacDonald, Gary Hooper and Richie Foran on the transfer list.
Up for sale
Chairman Ron Martin told the club's official website: "We have been unable to agree revised contracts with Peter, Simon and Nick.
"All three refused improved contracts and as a consequence we will transfer list them with immediate effect and use those proceeds to reinvest back into the squad.
"The football club won't be had to ransom by players and their agents; we would rather have players that truly wish to be here."