Students should be allowed to return home and continue their learning online if they wish to do so, say students and lecturers.
The National Union of Students and the University and College Union made the call as Covid-19 outbreaks hit almost half of the UK’s 130 universities.
NUS President Larissa Kennedy said the situation was exacerbating poor mental health and needlessly risking lives.
The government has stressed students will be allowed home for Christmas.
It was responding to outcry over students being confined to their halls of residence, many away from home for the first time.
Universities in local lockdown areas in the north-west of England and Scotland have been particularly badly hit.
Answering questions in the Commons on Tuesday, Gavin Williamson suggested a switch to full online teaching would only happen around two weeks before the Christmas break to allow students to self-isolate before returning to their family homes, if they wished to.
But the unions want the move to be made across the board now, before more students move into their accommodation.
Miss Kennedy said: “Over the past few months, students have repeatedly been encouraged to move, ensuring that universities and accommodation companies could collect tuition fees and rent whilst leaving thousands of students trapped in halls, with many struggling to access food, basic amenities and wellbeing resources.
“The ongoing uncertainty students face is exacerbating poor mental health, debt and needlessly puts lives at risk. Put simply – students deserve better.’
UCU general secretary Jo Grady said: “Ministers need to act now and tell universities to halt in-person teaching where possible and move the majority of work online, in line with other workplaces.
“They also have to guarantee funding for universities to safeguard institutions’ finances and protect jobs.
“If the government had followed our advice and made that clear financial commitment, universities could have spent the summer studying the science, working on a consensus about when to restart and, crucially, prepare properly for this term.
“Ministers government got in wrong at the start of this crisis. They need to act quickly now and not get it wrong a second time.”
In a statement, the two unions said they recognised the need to keep universities open, but that campus life needed a radical overhaul to keep us all safe and limit in-person contact.
“Those currently working and studying in our universities need a national strategy that fully recognises this risk, moves teaching online for the duration of this term, and ensures students can safely return home where possible.
“Students must not be forced to quarantine in halls of residence with no familiar support network, pastoral care and more serious restrictions than the rest of society.
“Staff must not be forced to carry out work on site that could be conducted more safely from home.
“Students must be allowed to safely return home if they wish to, without fear of financial penalty for leaving their student accommodation.”
On Wednesday, during a Downing Street briefing on the scale on UK’s second wave of infections, Boris Johnson paid particular tribute to students for enduring a “first term back at university unlike anything they could have imagined”.
In Scotland, a briefing from First Minister Nicola Sturgeon offered reassurance that students could return home for the Christmas break.
New guidance has been issued by the Scottish government which allows short home visits if there is a “reasonable excuse” such as a bereavement or family emergency.
Students can also move home and study from there permanently, but the default advice is to stay in university accommodation where possible.