MILLIONS of people across the UK have savings, investments, debts and income that they choose to keep hidden from their partners, according to new research from Prudential.

The survey, which examines attitudes to financial planning among co-habiting couples over the age of 40, finds that around 6.2 million (20 per cent) Brits have debts that they have not disclosed to their partners. The average value of the hidden outstanding debts is £9,546.

Fourteen per cent (4.3 million) of those surveyed also say they have private nest eggs of savings and/or investments, worth an average of £2,004, kept secret from their other halves.

When asked whether their partners know how much money they earn, one in seven (14 per cent) respondents say they do not. For nine per cent, that is because - despite living together - they never discuss earnings. The remaining five per cent, however, admit it is because they mislead their partners into thinking they earn more or less than they actually do.

When Prudential asked those who admit to having hidden debts how the debts arose more than a third (36 per cent) say they have borrowed money to cover everyday living costs.

Thirty-three per cent borrowed the money to pay off other outstanding debts, such as credit card bills, and six per cent say the debt arose from previous travelling costs.

Other reasons for having the hidden debts include overspending due to an emotional event (five per cent) and debts inherited from past relationships, such as joint mortgages (five per cent).

Among those who admit to having a secret nest egg, 22 per cent say the savings and investments are kept hidden to offer them financial security in case of a break-up.

A fifth (20 per cent) say their secret savings are there to cover the cost of items they wish to buy for themselves and 13 per cent are saving for something specific like a car or dream holiday.

Eight per cent of secret savers say they keep the funds hidden simply because they do not trust their other halves’ financial decision making.

Vince Smith-Hughes, retirement expert at Prudential, said: “Having conversations about finances may take some couples out of their comfort zones but keeping money hidden from a partner could be a real barrier to long-term security.

“Saving money, whether for a rainy day or a comfortable retirement, is imperative but doing it openly and honestly is the only way to ensure that savings are maximised between both partners.

“Having these conversations together is an important first step towards ensuring that you and your partner make the most of your combined funds and are, in turn, helping each other to secure the income and lifestyle you require in retirement.”