Almost four million families with children would be just one pay cheque away from losing their home if they lost their job, charity Shelter has warned.
A survey for the charity found that 44% of working families with children, equating to 3.8 million households across the country, could not pay their rent or mortgage for more than one month if they became unemployed and could not immediately find work.
Researchers also found that more than one quarter (29%) of families would face immediately being unable to afford their home if they lost their income amid low levels of savings, which would be around 2.4 million households if the figures were projected across the UK.
Despite signs that the economy is recovering, Shelter warned that millions of ordinary families, whose budgets are already at "breaking point", are at serious risk of losing their home if they face any sudden cut in income.
Liz Clare, who is a helpline advisor at Shelter, said: "Every day we see the proof that just one piece of bad luck, like a sudden job loss or illness, could tip any of us into a spiral that puts the family home at risk.
"Sky-high housing costs and stagnating wages mean that saving is becoming a thing of the past for many people. Most of us simply don't have enough money in the bank that we can rely on for long enough to get back on our feet."
Campbell Robb, chief executive of Shelter, said: "No matter how hard ordinary families work, in today's 'knife-edge nation' any drop in income can all too quickly put their home at serious risk.
"If you lose your job finding another one is hard enough, but without a stable place to live it's almost impossible.
"The Government must make sure the safety net is strong enough to stop families falling through the gaps, and going through the tragedy of losing their homes."
Shelter's findings were projected from research among more than 7,000 adults, of which over 4,500 pay a rent or mortgage.
The charity urged anyone who is worried about losing their home to get in contact with it for free, independent advice.
Citizens Advice Chief Executive Gillian Guy said: "There is little or no room for manoeuvre for people with stretched household budgets. Many are still feeling the effects of the recession as low wages and high costs means people face a daily battle to make ends meet. A month without a pay cheque because of an unexpected redundancy or work drying up can easily prove disastrous.
"The loss of a home is all too real a threat for those only just managing to keep up with the rent or their mortgage. Last year Citizens Advice saw a 16 per cent rise in social housing rent arrears and a 26 per cent increase in threats of house repossession for social housing tenants. Changes to Housing Benefit and Council Tax Support have put people in even more difficult financial positions. Enquiries about Discretionary Housing Payments to Citizens Advice Bureaux have risen by 110 per cent in just one year. More affordable homes need to be built to stop housing costs rising even further.
"Changes to emergency support mean many people don't know where to go for help, and for some, the help they need is no longer there. The availability of crisis funds must be made crystal clear to people who are at the end of their rope trying to meet living costs."