The ACV-listed pub at Norwood Junction is at the centre of a planning dispute between a developer and residents.
The campaign group say developer Peter Pendleton & Associates has converted The Ship into flats without planning permission after two failed applications.
The developer, who was unavailable for comment, is seeking retrospective planning permission with Croydon Council.
The pub’s ACV status means the owner must give the community group the chance to buy the property. Campaigner Mark Pickering said: “The only way residents can protect pubs and shops is to rally together and purchase them.
“We want to ensure that The Ship is refurbished sympathetically and is a pub that residents in the local area would like to drink in. Our pub survey has indicated that there is a demand in the area for a good quality CAMRA pub serving excellent food and drink.”
Campaigners have contacted the owner to advise him that they would like to purchase or lease the pub should it be put up for sale.
If the owner decides to sell, the group has six months to raise the money before it is placed on open market.
The campaigners hope to raise £200k through community shares valued at £50 per share. Shares will be topped up by a mortgage, grants and social enterprise loans.