More than 186,000 students entered clearing today in search of a rare vacant university place.
Competition is fierce and there are already clear signs that fewer places are available than last year.
Statistics published by the university admissions service Ucas showed there are 18,484 courses with vacancies at this stage - down from 32,000 overall last summer.
So far 186,494 applicants are eligible for clearing, around 27.7% of all applicants to university.
Last year, 140,908 students (22%) entered the process in total.
Some 47,600 students accepted places through clearing last summer, and the number is set to be smaller this year.
Earlier today, Universities Minister David Willetts apologised to students who may find themselves turned away.
Speaking at Ucas headquarters in Cheltenham, Gloucestershire, Mr Willetts said: "I think it is great that young people aim high, but it is competitive and sadly not every person who applies will get a place."
Asked what he would say to students left without a place at university at the end of the clearing process, he said: "I would say to them, we have done our best, there are more university places than ever before. I am sorry that they haven't got a place.
"And now, they have got a big decision to take. They can think about how they can strengthen their CV and reapply next year with something that might improve their chances.
"Alternatively they can look at options for FE colleges, going into work, going into apprenticeships. We are not writing them off, far from it, we are committed to offering them the best possible range of alternative opportunities."
Ucas said that 57.4% of the 674,037 people who applied to start undergraduate university courses this autumn have been accepted so far.
Asked how many students were likely to be left without a place at university, Ucas chief executive Mary Curnock Cook said: "It is always difficult to predict because it's not just the numbers of applicants and the number of places, it's also how those places are distributed around the system.
"Within a week or so we will have a pretty good idea of how many it is.
"It will be a high number but it always is a lot of people who don't get into university every year."
Students who failed to meet the grades required for their first choice of university, and their insurance offer, as well as those who declined all their offers or did not receive any, will be entered into clearing. This is the annual process that matches students without a place to courses with spaces.
The process is expected to be short this summer.
Many of the UK's top universities do not enter clearing, while others say the number of places they usually have available has been dramatically cut.
It has been predicted that between 170,000 and 200,000 applicants, including sixth-formers and older learners, could miss out this autumn.
Nicola Dandridge, chief executive of Universities UK, said: "Due to the increased pressure on places this year, competition is likely to be quite intense for the remaining courses. But we would urge applicants not to panic and to seek advice from Ucas and universities.
"Although we know that clearing will be more competitive than ever this year, we do know from Ucas that there were at least 18,000 courses, with numerous places available, in clearing this year. If applicants can be flexible, there is still a chance to gain a university place this year."