More than 12 million Britons are without a financial back-up plan, according to Bright Grey.
The provider's annual Financial Safety Net report found 60% of the adult population say they do not have any financial protection in place should the worst happen.
Four out of ten without insurance (43%) said cover is too expensive, but , for some it is not a priority, as 12% admitted that they prefer to spend on other things.
The average amount of savings that Britons can access immediately is £9,883, which is a £1,170 increase on figures from 2012, but still is unlikely to support a family for long.
Meanwhile, a quarter (25%) has not considered how they might cope with a ‘worst-case scenario', and a small minority plan to rely exclusively on government support.
Jennifer Gilchrist, senior product development manager at Bright Grey, said: "It is particularly concerning that a quarter of all people have not even considered what they would do in the event that something like this might occur.
"The high cost of living combined with a lack of adequate protection means that many could find life extremely difficult without a source of income."