Fear of debt makes poorer students more likely to leave university early than their wealthier counterparts, research suggests.
Poorer students feel they are less well advised, the study shows
The Joseph Rowntree Foundation found those from deprived areas had a disproportionate drop-out rate and were less likely to go on to more advanced study after their first degree.
They also more frequently delayed taking up their place, switched courses or repeated a year for non-academic reasons.
The co-author of the report, Professor Andy Furlong of Glasgow University, said: "Our work confirms disadvantaged young people are not enjoying as great a level of success in higher education as their peers.
'More help needed'
"They are often deterred by economic hardship and fear of debt from entering full-time education in the first place.
"But those who do make it to university or equivalent degree course are more likely to quit before reaching their academic potential.
"Better financial help, especially non-repayable bursaries, would enable more of them to complete their degrees, especially those who enrol for longer, more prestigious courses."
Lack of money and financial security limited poorer students' choice and length of course.
Fear of debt incurred through student and commercial loans appeared to be a greater deterrent to staying in higher education than the actual sums borrowed.
The researchers identified unfamiliarity with higher education as another reason for poorer students' shorter time in higher education.
Many of the students interviewed were the first from their family to go to university and felt they had been badly advised.
A high proportion of the 300 disadvantaged students whose progress was followed said they had had trouble fitting in and complained of isolation and low morale.
The National Union of Students (NUS) claims the fear of a £20,000 debt is putting 85% of young people off going to university.
It estimates this will be the amount owed by most graduates if the government raises annual tuition fees to a maximum of £3,000 by 2006.
NUS national secretary Penny Hollings said: "We have always said that debt and fear of debt deter bright students from poorer backgrounds accessing university.
"This report proves that financial barriers are key to prohibiting access.
"If the government really wants to widen access in higher education then it must re-think its student funding system and remove fees and debt from the equation."
The Conservative Party this week proposed scrapping the fees, with leader Iain Duncan Smith claiming they "penalised" poorer students.
The Liberal Democrate education spokesman, Phil Willis, said: "Fear of debt has created problems for young people from disadvantaged backgrounds in accessing higher education. It is as simple as that.
"More debt, and more money worries, make poorer students hesitate over the choices facing them over higher education."