UK consumers are struggling with almost £5bn of hidden debt, made up of rent arrears, and unpaid council tax and household bills, according to a report by thinktank Demos.

In a report entitled The Borrowers, the organisation said the sum, which equates to almost £200 a household, has been ignored by official debt figures, despite including the type of borrowing that was most likely to be detrimental to consumers.

Demos has created a "harm index" which ranks the impact of different types of debt according to their financial, emotional and social consequences, based on the experiences of people who have encountered each type of borrowing.

While mortgages tend to be a consumer's largest debt, and borrowing amounts to more than £1tn across the UK, Demos gave it a harm rating of just 23 out of 100.

By contrast, the types of debt people felt had the worst impact included payday loans, which scored 68 out of 100, council tax arrears, 62, utility bills, 57, and doorstep lending, 50.

Lenders pay a levy to the regulator, the Financial Conduct Authority, to fund financial education and debt advice for consumers, and the thinktank said loan companies that caused the most harm should pay the highest levy.

Demos is also calling for a traffic light rating system for all credit products and their adverts to alert consumers to the associated risks.

This information could include, for example, the proportion of borrowers who default on or roll over their original loan, the average amount repaid per £100 borrowed, and the risks of not repaying.

The hidden debt figure is based on data from property company LSL and debt charity StepChange, as well as government statistics on council tax arrears, and is supported by the results of a poll of almost 1,800 adults.

Demos said the lack of official figures on housing and utilities arrears created an incomplete picture of the national debt problem.

The report's author, Jo Salter, said: "There's a £5bn black hole in official debt statistics and our research shows just how arrears on rent, council tax and utility bills often have just as big a negative impact on people as payday lending.

"Deciding which forms of debt are 'bad' and need stronger regulation should not be based on industry definitions. It should be judged by looking at what types of debt cause people the most stress, disrupt their relationships with those around them, and undermine their capacity to help themselves."

The Consumer Finance Association, the main trade body for short-term lenders, said a traffic light system on payday loans would be meaningless.

"There is much in this report to welcome. It puts payday loans into context of overall consumer debt and throws light on to the much bigger, but previously unseen, problem debts that are challenging UK families," said its chief executive, Russell Hamblin-Boone.

"One person's credit is another person's debt, so we will continue our efforts to protect borrowers by ensuring our members operate to high standards.