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
A teenager from Bradford who was indoctrinated with 'chilling' extremist views has been jailed for plotting to go to Syria to fight for IS.
Georgina Ferguson was on a carriage behind the one that was bombed. This is her very personal story of 7/7.
HSBC has sacked employees who staged a mock Islamic State-style beheading during a team-building exercise.