Research from the Nuffield Trust shows people paying the charge contributed at least 60% more to the NHS budget in 2023/24 than the government estimated their healthcare would cost. 

The findings, published on Tuesday, come as several political parties have pledged to reduce immigration, raising concerns about the impact on NHS finances. 

The Immigration Health Surcharge is paid by most people applying for a UK visa. It costs £1,035 a year for adults and £776 for students and child dependants. 

Introduced in 2015 at £200 a year, the charge has become an important source of NHS income. It raised almost £2.5bn in 2024/25, accounting for more than 1% of the NHS budget, compared with 0.1% a decade earlier.

Nuffield Trust fellow Stelios Vassiliou said: 'Whether by accident, by design, or a combination of the two, the Immigration Health Surcharge has grown to a prominence that cannot be ignored.

'If the level of income from the charge was to fall back to that seen at its inception in 2015/16, the NHS would be left facing a shortfall in the billions, as it has grown reliant on immigrants in this group contributing substantially more to the NHS than they take out.

'Our analysis should give politicians pause for thought about this unforeseen, and possibly overlooked, consequence of changes to visa rules.'

Most visa holders must pay the surcharge upfront for the full duration of their visa, often three years. The money is then transferred to the NHS and spent in the first year, rather than being spread over the period it covers.

'The government needs to think carefully about what it's trying to achieve with the surcharge,' Vassiliou added. 'We need clarity on whether this policy is about migrants paying their fair share, topping up NHS funding, or discouraging migration in the first place.'