The private care sector has been ravaged by coronavirus outbreaks and huge numbers of deaths.
As a result, there's been a surge in the number of people seeking care in their own properties, as an alternative to going into a communal home.
A Leeds health scrutiny meeting was told on Tuesday that dwindling numbers of residents means that around a fifth of local care homes aren't taking enough cash to keep going long-term.
Those specialising in dementia care have been particularly badly affected.
Leeds City Council's director of adults and health, Cath Roff, said: "Before Covid, the average occupancy of care homes in Leeds was about 83 per cent, which is a bit on the low side.
"When we looked at it the other week, the figures we had suggested that there were now about 30 homes that were below a viable occupancy level for their long-term future.
"About half of those homes were specialised in supporting people with dementia, which doesn't surprise me.
"It's very difficult in those homes to manage infection in the same way, because it's very hard to stop patients moving about and touching their face.
"So they have been adversely impacted."
Ms Roff said that a lack of funding for homes is a significant part of the problem.
She added: "What we do have to do is make the case to national government that the Covid-related grants just aren't sufficient for us to provide what's needed to support the care home sector."
Labour councillor Paul Truswell described the situation as "frightening".
He added: "Adult social care was in a major crisis before Covid added to it.
"The idea we've got 30 homes that are not viable, or may not continue to be viable, is pretty terrifying."
Local Democracy Reporting Service