This equates to 2.4 million living together without a policy in place. In contrast, only 56% of married couples don’t have life insurance.

In particular, cohabiting families in London, the West Midlands and the East of England are the least likely of all regions in the UK to have life insurance. Those in Wales, the North East and Scotland are more likely to have life insurance.

Insurance giant Zurich said as cohabiting families do not yet enjoy the same legal rights as married couples, this leaves thousands of families at risk if their partner dies.

Cohabiting families have been the fastest growing household type over the last decade: the latest figures from ONS show that the number has more than doubled from 1.5 million to 3.3 million since 1996.

Peter Hamilton, head of strategic partnerships at Zurich, said: “The nuclear family is no longer the norm. Marriage may be on the cards for some, but many of us are now choosing cohabitation over tying the knot and this may well be the case for the rest of our lives.

“Whether we marry or live together, the needs of loved ones left behind shouldn’t be overlooked. Putting the right plans in place, if anything, is more important for cohabitees, where the law for those without a will is different to that for married couples. Life insurance can ensure the right money can go to the right person at the right time.”

See YourMoney.com’s Cohabiting couples: how to protect yourselves financially for more information.

Do you need life insurance?

Generally there are four scenarios in which you would need life insurance:

1. You have dependents, such as school age children
2. You have a partner who relies on your income
3. You have other family members living in a house with a mortgage you pay
4. You are concerned that relatives may not be able to cover your funeral expenses.