AGE UK Bexley is continuing to search for a new venue for its Welling Pop in Parlour.
For around 20 years Bexley Council has paid for the running costs of the property, in Bellegrove Road, and allowed the charity to use it free of charge.
But when the lease ends on June 23 the council will no longer foot the bill.
The building is used by more than 100 pensioners each week for activities including an Alzheimer's group and a hearing aid clinic.
At a meeting with service users yesterday (March 22) charity chief executive Paul Goulden said: "It is disappointing but there will be something for people in Welling.
"We don't want to lose the people who come to this place. We know what they get out of it and we enjoy having them here."
Age UK Bexley is looking at moving the parlour into a shop in the same road or to a sheltered housing scheme nearby.
A short term option is to use a room in the library, but this would mean not having a kitchen to provide lunches.
Mr Goulden added: "I'm bringing bad news but hopefully bringing a ray of light."
Ex Carers for Alzheimer's is a group which meets at the parlour every Monday.
Betty Larner, who helps run it, said: "It's been a God send. We have all been through the same sort of thing.
"You have times when you're down, like on anniversaries, but you come in here and cheer up.
"We don't let each other be miserable. I don't know what we would do without our afternoon here, I would be lost."
The 78-year-old added: "We would like to have stayed. They will lose members by moving but our lot will stay."
Age UK Bexley will hold another meeting with residents at the end of April.