Around one in five prospective students could defer going to university in the autumn if institutions are not “operating as usual” amid the Covid-19 crisis, analysis suggests.

An estimated 120,000 students may delay attending British campuses when the academic year begins in September and October, which would lead to a significant loss in tuition fee income for institutions, a report by London Economics for the University and College Union (UCU) warns.

The findings come as the University of Cambridge confirmed all “face-to-face lectures” will be moved online during the 2020-21 academic year to ensure social distancing can continue.

The University of Glasgow has also said large-scale lectures would be “impractical” at the start of the autumn term if the two-metre social distancing rule remains in place.

Around 5% to 6% of applicants usually defer their places each year – but the analysis estimates an additional 17% of prospective students will not enrol this year if universities are not operating as usual.

The analysis – based on a poll of 516 students who have applied to a UK university this year – also suggests there is a 25% chance that applicants will consider switching institutions through the clearing process.

Dr Gavan Conlon, partner at London Economics, said: “The analysis illustrates that there continues to be a huge amount of uncertainty amongst prospective students in respect of the potential higher education offer in September.

“If the current deferral rates as a result of the pandemic are borne out, then the financial consequences facing universities will be even more severe than those identified recently by London Economics.”

Universities across the UK are looking at how they will reopen campuses in the autumn – and whether some elements of courses will be held online rather than face-to-face – amid the Covid-19 pandemic.

The University of Manchester was the first to announce that all its lectures would be online for the autumn term.

The University of Edinburgh is planning to use “a hybrid approach” – a blend of on-campus teaching with online elements – as travel restrictions may prevent some students from being on-site.

Glasgow University told the PA news agency it is planning to restrict the numbers in lecture theatres, classrooms and laboratories in the autumn.

The start date for some postgraduate courses could be delayed but the university expects most undergraduate students to start in September. They anticipate courses to involve a “blend of remote and on-campus teaching”.

It comes after Nicola Dandridge, chief executive at the Office for Students, urged universities not to make any promises to students that everything will be back to normal in the autumn if this is not the case.

Addressing a virtual Education Select Committee on Monday, Ms Dandridge said students should be told what kind of experience they will receive when they accept a university offer.

We have now seen a few universities set out plans for the next academic year and there is no consistency. This only adds to the confusion for students

The Russell Group, which represents 24 leading institutions in the UK, has called for the UK Government to work with other governments to ensure there is a global recognition of online courses.

Some countries do not recognise international degrees with significant elements of online learning, which can be an issue for overseas students studying in the UK, the organisation has warned.

Jo Grady, general secretary of the University and College Union (UCU), said: “Universities are worried about loss of income and students being poached by other institutions. The Government needs to step in and underwrite income lost through fees and teaching grants and, in response, universities must promise to work together on plans for safely reopening and when to recommence face-to-face teaching.”

A Universities UK (UUK) spokesman said: “New and returning students can be confident that UK universities will be teaching high-quality courses this autumn while still prioritising the health and safety of students and staff.

“As we await further clarification and advice about next steps after lockdown, universities are already preparing for a range of scenarios – including periods of online and blended study in the academic year 2020-21.”

Universities Minister Michelle Donelan said: “I understand that this is an incredibly difficult time for students, so it is vital that universities are clear to students about how courses will be delivered in the coming year. I would urge students to think carefully about all their options and make informed decisions that best serve their futures.”