Most parents and students significantly underestimate the amount of money young people will end up owing if they go to university, a survey suggests.
University graduates owe on average £13,500
Sixth formers expect to owe about £6,000 when they graduate from university - less than half the average of what graduates actually owe.
The Association of Investment Trust Companies said it was a worrying stance among both students and parents.
The government said its financial package allowed for later repayments.
Students aged between 16 and 19 expect to graduate with debts of £6,199, according to research commissioned by the association.
This is just over £1,000 less than the £7,208 last year's respondents expected to owe, despite tuition fees of up to £3,000 a year being introduced in September.
Parents made roughly the same low estimate as students, saying that their child would owe £7,080, according to the survey of 914 parents and 421 children aged between 16 and 19, conducted in June and July.
However, this year's graduates owe an average of £13,500, the association said.
The AITC's Annabel Brodie-Smith said: "It's alarming that so few of tomorrow's graduates or their families really comprehend the financial implications of going to university.
"This year parents and future students have underestimated by a greater margin the amount of student debt they will face on graduation despite the publicity surrounding the introduction of top-up fees from September."
Higher Education Minister Bill Rammell said: "Our new student financial package is designed so that everyone with the ability and desire has the opportunity to go to university.
"Students can study first and repay back only when they are earning over £15,000.
"We have introduced non-repayable grants of up to £2,700, generous bursaries from universities and we know that graduates will earn on average over £100,000 more over their working life than someone with just two A-levels."