Skipton Group found that 98% of adults still living with parents could not afford to buy the average first-time buyer (FTB) home in their area on their own income.
In London, the East of England and the South West, fewer than 1.5% could afford to buy.
Removing the deposit barrier did not make a difference, with 97% still unable to afford a home.
More than nine in 10 would face housing costs above 45% of their income if they moved out, which is above widely accepted affordability limits, according to Skipton’s data.
Skipton Group, working with Oxford Economics, found that if parents could downsize, they could unlock an average of £72,400 in equity or save £2,400 a year in rent.
For lower-income households, this equity could be up to 60% of their non-property wealth.
More than half (51%) said they felt a sense of lost youth, and 70% had never moved out.
Most had no clear path to independence.
Nine in 10 hoped to leave home, but 82% of those able to save said they were still far from getting a deposit together.
Stuart Haire, CEO of Skipton Group, said: “This data lays bare the systemic failure of our housing ecosystem.
“It’s a failure that is locking millions of young people out of independence, home ownership, and long-term financial stability.
“When 98% of adults living with their parents can’t afford to leave, they’re not just facing a housing crisis – they’re facing a crisis of opportunity.”
Haire added: “At Skipton Group, we are unwavering in our commitment to make home ownership more than a distant aspiration.
“Whether through our lending, our estate agency network, or through research like this, we are determined to help people take meaningful steps towards a home of their own.”
