A fifth of households said they have no emergency cash while another 12 per cent said they have less than £250 for a rainy day.
It is generally recommended to build up a minimum of three months take-home pay as a "salary cushion", typically £5,756.
Some 28 per cent of those who took part in the survey said they would be unable to cover rent or mortgage payments if they unexpectedly lost their income.
One in 10 said they would be forced to rely on a credit card, personal loan or an overdraft.
More top news
David Cameron will use a speech today to set out plans for patients to be able to access hospital services seven days a week.
The young Labour supporter seen celebrating an impromptu photo with Ed Miliband has defended her desire for an early campaign selfie.
An unsettled weekend of weather forecast as conditions turn wet and windy from the west tonight and slowly clear eastwards through tomorrow