Students are running up substantial debts but earning less than they expect on graduating, research indicates.

The authors of a report say that government ambitions to push half of all school-leavers into higher education could be to blame for the mismatch between expectations and reality.

On average, students misjudge their starting salaries by more than £2,000, according to the research led by John Jerrim, a PhD student at Southampton University's department of social statistics.

New graduates were paid an average of £16,600, rather than the £18,600 that they had expected. Some had been ambitious enough to anticipate a six-figure pay packet.

Students now commonly graduate with £30,000 of debt, accumulated through tuition fees and living expenses. The research raised questions about ministers' assumptions that a degree almost guarantees a decent salary. Its authors said: “Overestimating future wages could lead some students to mistakenly choose to go to university, when they will not receive the benefit they expect.

“This may be further exacerbated by government policy that encourages young people to go to university, highlighting the magnitude of possibilities the student will have on graduation, that never actually materialise.”

Bill Rammell, the Higher Education Minister, said recently: “A university degree is a great way to get a good, well-paid job, and to get on in life - a picture that only improves over time. Graduates can expect to earn considerably more over their careers than those without a degree.”

The survey of more than 3,000 students across 70 universities found that the average student overestimated his or her first annual wage by 12 per cent. Those from the elite Russell Group universities were marginally more unrealistic, anticipating 13 per cent (£2,165) more than they would earn.

Black and Asian students overcalculated by 14 per cent (£2,332), while first-year students estimated that they would earn 16 per cent (£2,500) more, perhaps because “students who have just made the decision to invest in university education have especially inflated expectations”. Medical students were rare in underestimating how much they would earn. There was a significant difference in expectations based on wealth and privilege, with the children of high-earning parents expecting better salaries. The authors said: “Students may use their parents' income as a benchmark for their future salary, or think their parents have connections in the labour market that will help secure them a lucrative job.

The report concluded: “Students are using credit markets, in part, to smooth their consumption over time. An oversupply of easy, cheap money could well lead some individuals into difficulties later in life. Young people may be entering university based on unrealistically high expectations.”

Students also gather thousands of pounds worth of equipment. Research by Ensleigh insurance company found that a student's laptops, mobile phones and similar goods were worth an average of £6,000.

Case Study: Anna Griffiths

Ms Griffiths, 21, graduates today but is not walking into her dream job. Instead the comparative literature graduate, who wants a career in fashion journalism or in the saleroom, will work at a boutique this summer.

Anna, who went to King's College London, said: “I certainly didn't think it would be this hard to find work. I thought once I had a degree I would automatically get a job. But my friends and I are finding there's nothing available and no one is taking anyone on. I'm going to use this year to get as much experience as I can. Hopefully by next year the economy will be in a better state.

“I didn't think about my starting salary when I began my degree, but for my first job I would want at least £15,000.”

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