Six years ago, as the Coalition’s Special Adviser on Universities and Science, I was in the midst of fraught discussions with the Home Office about international students. The Immigration Minister at the time, Damian Green, was about to make a speech that seemed to exaggerate the cost of hosting international students in the UK.

The Home Office suspected international students were clogging up our roads, filling up our hospitals and houses and even taking places at our schools for their children. We argued, in contrast, that they seemed to contribute far more to the UK—for example, via their spending on tuition fees and living expenses—than they cost. Typically, international students are fairly young, arrive without lots of expensive dependants and live in shared occupancy accommodation, which is often purpose-built for the sole use of students.

But neither the Home Office nor us had hard numbers to back up our arguments. Damian Green, to his credit, ended up delivering a speech that avoided blaming international students and instead called for a new debate. He argued: “there is scope for further examination of whether and to what extent foreign student tuition fees boost the UK economy and crucially how UK residents ultimately benefit from that.”

Since then, relations between UK universities and the Home Office have been in the deep freeze. For example, successive immigration ministers, under pressure from Theresa May as Home Secretary and then Prime Minister, have refused to remove international students from the government’s target to reduce net inward migration to below 100,000. There have also been various rule changes that have imposed new obstacles in the path of those contemplating studying in the UK. But one thing has not happened: the debate has not become more evidence-based in the way that, back in 2012, Damian Green said it should. In other words, there has been lots of heat but not much light.

At the Higher Education Policy Institute, we became so bored waiting for this to change that, in the middle of 2017, we joined with Kaplan International Pathways for a project with three parts. We asked, first, for an updated calculation on the gross benefits to the UK of hosting over 400,000 international students. We also requested a figure for the costs associated with those students, to enable a calculation of the net benefits. Additionally, we asked for the data to be produced on a local basis, including for each parliamentary constituency.

When London Economics crunched the numbers for us, they found the annual gross economic benefits of international students—including tuition fees, other spending and economic knock-on effects—to be £22.6bn. On average, over the length of their courses, that is £87,000 for each EU student and £102,000 for each non-EU student. Meanwhile, the public costs—including education, health, social security and even areas like defence—are just £2.3bn. On average, that is £19,000 for each EU student and £7,000 for each non-EU student. Removing the costs from the benefits still leaves a huge total of £20.3bn or £68,000 for each EU student and £95,000 for each non-EU student.

“Perhaps I am naive, but I have always thought the policy will eventually change”

The impact is positive in each part of the UK, every local authority area and every constituency. For example, students in Sheffield Central generate £226m for the UK economy, students in Cardiff Central generate £151m, students in Glasgow Central generate £135m and students in Belfast South generate £29m.

The figures are huge, yet they are not as big as they could be. The number of international students in the UK has stagnated in recent years, while other countries have forged ahead. In this growing global market, to stand still is to go backwards against our main competitors. Moreover, Brexit will almost certainly mean fewer people come here from mainland Europe to study because EU citizens may no longer be entitled to pay lower fees and may lose access to tuition fee loans.

Soon after we set our work in train, the Home Office commissioned their own Migration Advisory Committee (MAC) to look at international students. We welcomed this, will be submitting our work to them and believe our data are the most detailed information the Committee will receive in response to their call for evidence.

It would be in the interests of students, universities and the UK as a whole if the government were to stand on the shoulders of the MAC and change their approach so that, once more, we can roll out a red carpet for people who want to come here to learn.

Perhaps I am naive, but I have always thought the policy will eventually change. We are, generally, a well-governed country with policymakers who like following evidence and it is rare to find an issue where so much of the evidence is on one side of the debate.

Finally, although international students bring a financial boon to the UK, we must not forget the benefits are not just financial. Other work we have produced in the past shows people generally think they benefit from studying alongside people from other countries. We have also shown that more serving world leaders were educated in the UK than any other country. So the soft power benefits are enormous. There is no excuse for putting them at risk.