Union leaders have launched a campaign against planned cuts to a fund which supports the homeless, elderly and victims of domestic violence, warning that councils face losing tens of millions of pounds.
Unison said more than one million people benefit from the Supporting People programme, including those at women's refuges, rough sleepers and people with mental health problems.
But 10 councils face cuts of more than £5 million each, including Manchester, Liverpool, Leeds and Nottingham, 22 face cuts of up to 20% and seven are having funds reduced by between 40% and 50%, including West Berkshire, York and Bournemouth, said Unison.
Dave Prentis, Unison's general secretary, said: "All over the country, Supporting People grants fund women's refuges, providing a haven for victims of domestic abuse.
"They help keep people who have fallen on hard times from sleeping rough, and give people with mental health problems a roof over their heads.
"More than 800,000 elderly people rely on services funded through Supporting People. Drastic cuts will mean shelters shut, and beds lost, pushing vulnerable people onto the streets or leaving them without the help they need."
A Department for Communities and Local Government official said: "The importance of the Supporting People programme in helping vulnerable people was clearly recognised in the Government's Spending Review where we committed to investing £6.5billion over the next four years. Nationally for every pound of Supporting People funding provided last year, 99p will be provided this year.
"The Supporting People ringfence was removed in April 2009 which gives local authorities maximum flexibility to meet local priorities. While we recognise the challenges councils are facing, we do expect to see them match the Government's commitment to help the most vulnerable people in society.
"There is no excuse for councils to be targeting any disproportionate spending reductions on programmes that support the most vulnerable people in their communities."
