The true number of young people who are homeless far exceeds government figures, according to a major new study by housing experts at Cambridge University being released on Monday.

Some 83,000 homeless young people have had to rely on councils and charities for a roof over their heads during the past year – more than three times the 26,852 young people recorded in homeless figures released by the Department for Communities and Local Government. And there are about 35,000 young people in homeless accommodation at any one time across Britain.

The “worryingly high” levels of young people using homelessness services across Britain is “a minimum estimate and it is likely that in reality more homeless young people access support across the UK”, the research said.

The study, by Cambridge University’s Centre for Housing and Planning Research, was commissioned by the homeless charity Centrepoint and provides the most comprehensive picture of youth homelessness to date. It draws on official figures in conjunction with examinations of 40 local authorities and a national poll of more than 2,000 16- to 25-year-olds.

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The research looked at homelessness during the course of a year, including rough sleeping, staying in hostels and “sofa-surfing”.

Government figures do not capture those who do not meet narrow criteria for being homeless which would force councils to help them. Many homeless people do not come into contact with their local authority, and those that do are often considered to be “intentionally homeless” or not in a “priority need” category such as being under 18 or pregnant, the study says.

More than one in seven young people (17 per cent) have slept rough, including in places such as cars or squats, during the past year, according to a ComRes survey done for the study. “When the poll data was scaled up to reflect the wider population, an estimated 1.3 million young people aged 16 to 24 have slept rough during the past year,” said the research.

Collecting “coherent national data on youth homelessness” is essential if the true scale of the problem is to be understood and funded accordingly so that young people receive the support they urgently need, the research concluded.

“Successive governments have been making policy in the dark as they have failed to grasp the sheer scale of youth homelessness in the UK,” said Balbir Chatrik, policy director of Centrepoint. “We’re seeing the consequences of funding decisions based on this lack of knowledge which have placed extreme pressure on charities and local authorities, with the majority of hostels full or oversubscribed.

According to a ComRes survey more than one in seven young people (17 per cent) have slept rough (Getty)

“Young people typically find themselves facing homelessness through no fault of their own. As a society, we owe them a national safety net devised from more than just guesswork.”

Responding to the findings, Campbell Robb, the chief executive of Shelter, said: “This research paints a grim picture of youth homelessness in the UK and demonstrates that the Government’s current plan to cut housing benefit for 18- to 21-year-olds could be nothing short of catastrophic – as it’s this which helps to pay for the hostel beds that keep young people off the streets.

“If the Government really wants to help young people, its first priority should be to invest in the safe, secure and genuinely affordable homes that are so desperately needed, rather than stripping away the threadbare safety net they have at the moment.”

This comes amid warnings in recent weeks that Britain is heading for a housing crisis, with the numbers of households in temporary accommodation at almost 65,000 – the highest since 2008.

Communities Secretary Greg Clark, speaking at the Local Government Association’s annual conference on Friday, admitted that young people are being “exiled” from the places they come from to “find a home that they can afford”.

In a statement, a government spokesman said: “Since 2010, we have increased spending to prevent homelessness, making over £500m available to local authorities and voluntary sector.”

Mo Ibrahim came to Britain five years ago and in 2013 was thrown out of the family home

Other initiatives to help young homeless people include £14m to support 10,000 vulnerable individuals in privately rented homes, £15m to turn around the lives of 1,600 vulnerable homeless, and £40m shared among projects to support young people to work and study and hostel accommodation to get them off sleeping on the streets.

Mo Ibrahim, 22, from London, came to Britain five years ago and in 2013 was thrown out of the family home.

“I used to sleep at the back of my mum’s house in a park on a bench and it was really horrible. I was lucky that it was summer. I would go to the shelter to have something to eat. When I used to sleep over there I’d worry that someone would something to me.”

After two weeks of sleeping rough, Mo managed to get a place at Centrepoint.