International students in the United States would face a US$100,000 price tag to work a science job in the country after graduation under a proposal made public yesterday by the administration of US President Donald Trump.

The proposed rule would require academic institutions to foot the bill for a work programme called optional practical training (OPT), which allows overseas students to work in the United States for up to 3 years after finishing an undergraduate or graduate degree.

Some 420,000, or roughly one-third, of international students participated in OPT in the 2025–26 academic year, making it the largest pipeline of global talent into the US workforce.

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The US Department of Homeland Security (DHS), which issued the proposed rule, stated that it is meant to “combat fraud, strengthen the integrity of the immigration system, and protect U.S. workers”. The DHS projected that if the rule were finalized, OPT enrollment would drop by as much as 44% and universities would pay between $8.4 and $16.5 billion annually.

An analysis¹ of the rule’s effects on OPT enrollment by Michael Clemens, an economist at the Johns Hopkins School of Government & Policy in Washington DC, projects that the number of students who enroll after a bachelor’s degree would be halved, and that enrollment by those with master’s degrees would be virtually eliminated. Clemens also noted that OPT is especially important for international PhD graduates in science, technology, engineering and mathematics (STEM) fields, drawing roughly 70 percent of them in 2022.

The proposed rule is the latest in a series of Trump administration attempts to restrict immigration, which have already limited the country’s ability to recruit scientific talent. In 2025, for example, Trump announced a $100,000 levy on a visa reserved for researchers and other highly skilled foreign workers. As a result, new applications for those visas plummeted by 90%, according to the US Citizenship and Immigration Services.

If the new proposal and related restrictions are implemented, the combined measures “will obliterate the pipeline” of talent, says Clemens. In a separate analysis commissioned by the US National Academies of Science, he and his colleagues found that the size of the entire US STEM workforce would drop by 6–11% over a decade if all the administration’s proposals were implemented.

A spokesperson for the DHS said that the $100,000 charge “would strengthen program oversight while addressing concerns of fraud and abuse”, but did not respond to questions about the impact to the international STEM talent pipeline.

High cost

The OPT programme has expanded dramatically over the past decade, as international students have taken advantage of it to work at top tech companies such as Google and Amazon. Last year the number of recent graduates enrolled rose by 14%, even as the number of new international students dropped, notes Violet Buxton-Walsh, an immigration policy researcher at the Institute for Progress, a non-profit think tank in Washington DC. Despite restrictions on immigrants, “[t]here are very few who have better options than staying in the U.S.,” she says.

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The administration’s proposal, first reported by the Wall Street Journal, would require graduates to pay a $70,000 charge for their first year of OPT; STEM graduates would pay an additional $30,000 for a two-year extension.

Without the lure of OPT, the number of international students in the United States is likely to drop sharply, multiple scholars told Nature. As a result, Clemens projects that US colleges and universities could lose a combined $2.5 to 4.2 billion each year in tuition and other revenue.

Ina Ganguli, an economist of science and innovation at the University of Massachusetts Amherst, says the impact goes beyond numbers and finances. “It will change the type of students who are going to come to the US”, she says, because top prospects have the freedom to look elsewhere.