It was also revealed that 14 per cent of homeowners do not have home contents insurance, while 17 per cent of those with cover are unsure if they have a policy which covers the total value of their contents.
Robin Bailey, Nationwide's insurance editor, said that it was surprising that people take "such a gamble" on their personal belongings.
"You never know what is around the corner and for that reason it is vital that people are prepared by having adequate insurance," he added.
Customers were also recently warned by Tony Levene, the author of Which?'s new Money Saving Handbook, to ensure they make an "informed choice" when shopping around for insurance products.
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