Men assure nearly twice the sums as women with critical illness cover on average, IRESS data shows.
The average sum assured for males is £10,986, 90% higher than £5,790 for women.
The typical amount covered by men is also 50% higher with combined life and critical illness and 53% higher with life cover.
Dave Miller, IRESS executive general manager, commercial, said: “It is generally accepted that men have more protection cover than women.
“This is for a whole range of reasons including the fact that men, on average, are paid more than women, and we tend to find that the main bread-winner in a couple tends to have more life cover. That’s to be expected.
“However, while we’re well aware of these differences in gender protection needs, I was still taken aback by the size of the difference revealed through our data.
“For me, it suggests that women are at a far greater risk of being under-insured than men.”
The pay gap, currently around 17.9% for full and part time workers according to ONS data, and other societal factors go some way to explaining the reasons behind the gender differences in protection sums assured, however IRESS said the extent of the difference is surprising.
Averaged across the three H1 periods, women accounted for 46% of protection sales and 54% were for men, so there is no significant gender difference in the actual number of men and women seeking protection cover.
The data comes from the first half of the year in the past three years.