The traditional path to adulthood and independence is breaking down for young people, with many relying on their parents for support until well into their 20s, according to a new report.

A study for the government-sponsored National Family and Parenting Institute finds that a drive to get more young people to go to university, together with the decline of jobs for youngsters and higher house prices, is ensuring young people stay dependent for much longer.

The report also warns that while middle-class youngsters can usually rely on their parents to support them financially through higher education and beyond, many of those from less well-off backgrounds are more vulnerable.

Many families may be unable to afford continuing help, the research concludes, while others may simply not expect to "keep the door open" for young people to return.

Many parents are also funding other children through university or caring for elderly relatives, and have little cash to spare to support a twentysomething who cannot fly the nest.

The result, according to the study, is polarisation between those young people who take the "slower routes to adulthood", usually by staying on in education and delaying employment and starting a family, and others who enter an eroded youth labour market at 16, risking unemployment or insecure and badly-paid work.

Gill Jones, emeritus professor of sociology at Keele University and author of the report, said young adults were being caught between family law, which regards parental responsibility as ending at 16 or 18, and a state safety net which denies young people full support until they are in their early or mid-20s.

While child benefit, for example, is not paid to parents beyond 18 at the latest, jobseekers' allowance is not paid in full to young people until they reach 25, and the full adult rate of the minimum wage kicks in at 22.

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