Universities are being urged to block certain websites and use smarter cheating detection software to crack down on students buying essays online and then passing them off as their own.

The university standards watchdog has issued new government-backed guidance to help address “contract cheating”, where thousands of students are believed to be paying hundreds of pounds at a time for written-to-order papers.

The Quality Assurance Agency (QAA) made a series of recommendations including providing more support for struggling students, introducing a range of assessment methods to limit cheating opportunities, blocking so-called essay-mill websites and adopting smarter software that can tell if there is a difference in style and level of ability between a student’s essays.

The proposal comes after Jo Johnson, the universities minister, called for advice to help address the problem.

Johnson welcomed the new advice, saying: “This form of cheating is unacceptable and pernicious. It not only undermines standards in our world-class universities, but devalues the hard-earned qualifications of those who don’t cheat … That is why I asked the Quality Assurance Agency to look at this issue and introduce new guidance for students and providers.”

The chief executive of the QAA, Douglas Blackstock, said: “Paying someone else to write essays is wrong and could damage their career. Education providers should take appropriate action to tackle and prevent this kind of abuse.”

Research by the QAA found that there are now more than 100 essay-mill websites in operation. The amount they charge is dependent on the complexity of the essay and tightness of deadline, but a PhD dissertation can cost as much as £6,750.

In Britain it is left to individual institutions to develop their own plagiarism policies. But the QAA said it wanted a consistent approach among higher education providers to tackle the problem. It called on universities and colleges to record incidents of this and other kinds of cheating to help build a clearer picture of the scale of the problem.

Thomas Lancaster, an associate dean at Staffordshire University and one of the UK’s leading experts on essay cheating, said the new guidance was a move in the right direction but that to truly tackle the problem a change in the law was needed.

“There are still too many people out there who are setting assessments where a student can just go online, pay a writer who might not even be a subject specialist, hand the result in and come away with a good mark,” he said.

He added: “I fully support universities reviewing their academic integrity processes to make sure they’re up to date and fair to students … But we also need to send a strong message out to the companies who are doing assessed work for students. Earlier this year, Lord Storey put forward a proposal to the House of Lords to make this activity illegal. It’s time for a renewed push to get that legislation through and to also ban the advertising for essay mills that is drawing students to use these services.”

Amatey Doku, vice-president for higher education for the National Union of Students, said that institutions and the government must look at the underlying issues behind the rise in these websites.

He said: “Students are under immense pressure. Their degrees will leave them with debt of around £50,000, which will affect them for most of their adult lives. The pressure to get the highest grades in return for this can be overwhelming. Insufficient maintenance funding also means that around 70% of students must now take on paid work alongside their studies, which can leave little time for academic work and study. It is easy to see how an essay-mill website could feel able to con students. Many websites play on the vulnerabilities and anxieties of students.”

He added: “We would urge those who are struggling to seek support through their unions and universities rather than looking to a quick fix.”

A Universities UK spokesperson said: “Universities take plagiarism and cheating extremely seriously. Submitting work written by someone else is cheating and devalues the efforts of students who work hard to achieve their degrees … Such academic misconduct is a breach of an institution’s disciplinary regulations and can result in students, in serious cases, being expelled from the university.”