Thousands of pounds more was spent by institutions on flights, often first or business class, and hotels for vice-chancellors, according to the University and College Union (UCU).
It claimed that in general, bosses enjoyed salaries and benefits worth around 6.5 times more than the average wages of staff.
The union, which obtained data on pay packages through freedom of information requests and publicly available data, raised concerns about "huge disparities" in pay, and called on the Government to step in and enforce proper scrutiny of senior university leaders' pay.
UK universities and colleges were asked a series of questions about vice-chancellors' pay, including benefits and pensions, as well as money spent on air fares, hotel accommodation and personal expenses, for the year 2015/16.
The union's analysis of the data revealed that the average pay packet, including benefits, pension and bonuses, for a university chief, based on data from 151 institutions, was £277,834, up 2% on the previous year.
A number of universities changed their head of institution during the course of the year, which could affect the figures.
Southampton University paid out the most, at £697,000. This takes into account a change in vice-chancellor at the institution, with Professor Sir Christopher Snowden taking over from Professor Don Nutbeam in October.
The university said it had been informed by Prof Nutbeam in 2014 that he intended to retire in autumn 2016, or earlier if a replacement was found. Prof Sir Snowden was appointed and available quicker than planned, allowing Prof Nutbeam to leave at the end of September 2015. He was paid to the end of his contract.
Dr Gill Rider, Southampton's chair of council said: "Sir Christopher Snowden has had a distinguished and successful career in the higher education sector and we are delighted that he accepted the important leadership role as president and vice-chancellor.
"We believe that his salary is reflective of the quality and high level of expertise which he brings to the University of Southampton, a large, complex, international institution with over 24,000 students, 6,500 members of staff and a turnover in excess of £550 million per annum."
Professor Dame Glynis Breakwell, vice-chancellor of Bath University had the second highest wage package at £451,000, UCU calculated.
A Bath spokesman said that the salary and conditions were independently determined and "comparable with that of long-standing vice-chancellors in other successful universities".
The average spend on air fares for vice-chancellors, based on information from 137 universities, was £7,762. Around two-thirds (65%) of flight spending was on business and first class airfares.
And £2,982 was spent on average on hotel accommodation for university chiefs, similar to last year. This was based on information from 135 institutions.
Hotel expenditure was similar to last year, and there was a drop in money spent on flights.
A different number of institutions responded to the questions last year.
UCU general secretary Sally Hunt, said: "Those at the very top in our universities need to rein in the largesse that embarrasses the sector and the Government needs to enforce proper scrutiny of their pay and perks."
She added: "Unless the Government finally steps in, we believe many vice-chancellors will continue to spend public money and students' fees with impunity.
"The huge disparities in the levels of pay and pay rises at the top expose the arbitrary nature of senior pay and perks in our universities."
A Department for Education spokesman said: "We are clear that in order to achieve efficiencies universities should demonstrate restraint in senior pay. We remain concerned about the substantial upwards drift of salaries of some senior leaders."