The council said it would still have 34 residential beds
A charity for the elderly has said the closure of three residential homes in East Sussex will lead to people becoming isolated in their houses.
The county council is to close Gilda Crescent in Polegate, Grangemead in Hailsham and St Anthony's Court in Eastbourne, saving £1.7m a year.
It said it would still have three homes, with 34 beds, and will spend the savings on services for people at home.
But Age Concern said people might feel their homes were "almost like prisons".
The three homes, which the council agreed to close on Tuesday, provide interim and respite care for people discharged from hospital before they return home.
"These are people who are in the high needs level of care and support," said Steve Hare, of Age Concern.
"Respite is also for the carers, who are often very elderly and frail themselves."
He said that residential homes provided a social environment and a chance to assess needs that might not be picked up at home.
"People do want that extra support away from home where they can take a break and carers can get some respite," he said.
Director of adult social care, Keith Hinkley, said the county council was going to "recycle" the savings from closing the homes.
"We are not withdrawing services but finding different way to provide care," he said.
"A number of these services are going to be recommissioned with the private sector.
"We feel confident that we will have the right number of beds to provide interim support but we will also have more money to provide a broader range of community services."