Of the people who do not have insurance, 35 per cent feel that it is not necessary, while 14 per cent state that they cannot afford it.
Neil Laird, Sainsbury's Home Insurance manager, said the findings were "remarkable".
"Home insurance does not have to be expensive. You can spread the cost over the course of a year and some insurers, including ourselves, will not charge for this. There are also some great discounts on cover available at the moment," he added.
Previous research by Sainsbury's Bank also found that just over four million people also did not take out travel insurance when they last went abroad on holiday.
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