More than one fifth of UK adults have secret debts they’re hiding from their partners or family, according to research for Debt Advisory Centre.

The survey found that 22% (11 million UK adults) have borrowed money in the past or still owe money without the knowledge of their loved ones.

Being secretive about debt was particularly common among younger and middle-aged borrowers, with a third of those aged 25 to 34 and 31% of 35 to 44-year-olds admitting to hidden debts.

Londoners were also far more likely to stay quiet about owing money than borrowers from anywhere else in the country, with 32% admitting to concealing their debts. However, those living in the South East – where costs are similar to London – are the most open about borrowing money, with only 16% admitting to secret debts.

Although half of those keeping quiet about their debt had to repay less than £1,000, just short of a third owed between £1,000 and £5,000; 9% owed from £5,000 to £10,000; and one in 10 owed more than £10,000.

Ian Williams of the Debt Advisory Centre said: “We all occasionally spend money when we know our partners or parents won’t approve. It may seem harmless – and certainly easier – to keep quiet about it to start with, but if your spending involves borrowing the money through a credit card or payday loan, this adds another layer of risk.

“It’s impossible to work out and stick to a budget for the household if one member of the family is not being open about their outgoings and how much money they owe.

“If your secret borrowing has become a secret debt problem then you need to address it. The first step is always the hardest, but speaking to a professional debt advisor and sharing the problem with a friend or loved one are the first steps on the road to recovery.”