Just one in six of the nearly nine million people estimated to be trapped in a spiral of severe debt in the UK is getting help to break free, Government-backed body the Money Advice Service (MAS) has found.
Around 8.8 million people are "over-indebted", meaning they have fallen at least three months behind with their bills in the last six months or they feel their debts are a heavy burden.
But just 17% of this group said they are getting advice to help them deal with their debt, while around two-fifths (40%) said they did not feel able to talk to their creditors and 44% did not know where to turn for help, the research from more than 5,000 people found.
Meanwhile, around one fifth (21%) of those the research classed as over-indebted, equating to 1.8 million people across the UK, did not recognise that they had a problem. A further 11% were not concerned about being in debt , the report, titled Indebted Lives, found. One in eight (12%) over-indebted people said they were thinking about trying to get help soon.
The report also identified the UK's five most over-indebted areas as Hull, Nottingham, Manchester, Knowsley and Liverpool. Around two-fifths of adults in all these areas are struggling with debt.
Three-quarters (75%) of the estimated 8.8 million people with severe debt problems are under 45 years old and nearly two-thirds (64%) are women .
Some 74% of those with severe debt problems said they are unhappy and 83% wanted to claw their way back into financial health as soon as possible.
Around four million people are thought to have been struggling to pay their bills for more than a year and just under half (48%) of those with severe debt had to forego basic necessities.
The report used information from credit checking company Experian to build a profile of those who have sunk badly into debt. Families dependent on benefits made up around one fifth (20.2%) of those who are over-indebted, while "worried" working families who find being in debt a constant burden accounted for a similar proportion (19.4%).
Nearly one in 10 (9.8%) of those with bad debts were identified as people who are working for the first time and one in eight (11.3%) are struggling students. Some 1.1% of this group are people eking out an uncomfortable retirement.
Almost three-fifths (58%) of those with severe debts were found to be in employment and nearly half (48%) live in a privately-owned home.
The MAS is an independent body set up by Government and funded by the financial services industry. It offers free money advice and has statutory responsibility for coordinating debt advice in the UK.
It is sharing its findings with other bodies across the debt advice sector as part of discussions to improve consumers' access to services.
Caroline Rookes, CEO of the MAS, said: "Millions of people could escape their spiral of debt by accessing free advice.
"However, this study presents us with a fundamental challenge: the majority of people with debt difficulties do not seek advice.
"This is the first time we've had such a detailed understanding of the complexity of their lives. So now, armed with greater insights, we will work with advice agencies, creditors and public bodies to help as many people as possible access free, high-quality, debt advice."
Here are the eight groups of the "over-indebted population" identified by the report:
:: Struggling students (11.3% of the over-indebted population, equating to one million people across the UK)
The report said this group does not recognise any need to engage with debt advice, with the majority, 78%, not currently getting or thinking about getting advice in the near future.
But almost three- quarters of this group are behind with credit commitments.
:: First time workers (9.8% of the over-indebted population, equating to 900,000 people across the UK)
The report said there is slightly more engagement with advice than the struggling students segment, but it still remains low.
It suggested that tapping into this sector's ambition of getting on the housing ladder might help them to engage better.
:: Optimistic young workers (12.5% of the over-indebted population, equating to 1.1 million people across the UK)
This group was found to recognise the need for debt advice, with 30% of people either receiving or about to receive advice.
The report said that many people in this group are beginning to face key life events, such as buying a house, or having a baby, meaning they are becoming increasingly aware of their situation .
They are more likely to listen and take action, even though many of them currently feel in control.
:: Low wage families (9.3% of the over-indebted population, equating to 800,000 people across the UK)
This group also recognises they need help, with 32% already receiving or about to get advice.
The report said this group said they wanted to receive fewer calls from creditors and they could benefit from more information about prioritising debts.
:: Stretched families (16.3% of the over-indebted population, equating to 1.4 million people across the UK)
These are people who work hard and have little leftover cash for savings or luxuries. They are resigned to their situation, with 54% saying that living in debt is something they are used to.
The report said this large group needs information or education to tell them what advice services can do to help them and so encourage them to take it.
:: Worried working families (19.4% of the over-indebted population, equating to 1.7 million people across the UK
These people may be home owners and could be trying to support their children financially.
They are more likely to be taking advice and to identify they have a problem. These families find being in debt a constant worry and they are keen to find a solution through access to debt advice.
:: Benefit dependent families (20.2% of the over-indebted population, equating to 1.8 million people across the UK)
The report found "widespread disengagement in this group, with three-fifths (59%) of those surveyed having no plans to seek advice.
Many felt that their situation is "helpless or inevitable".
This segment has a clear and immediate need for debt advice, being the group that is most likely to have missed payments, the report found.
:: Uncomfortable retirees (1.1% of the over-indebted population, equating to 100,000 people across the UK)
People in this group have the most divergent views about seeking advice. While one fifth are currently getting advice, nearly one third (30%) cannot see themselves ever getting advice.
For many older people in this group, there is a shame, stigma or feeling of guilt associated with being over-indebted and they will be more reluctant to reach out for help, the report said.
But offering them generic advice about how to make the most of their money may appeal to them.