Since the beginning of 2021, the United Kingdom has experienced a significant increase in net migration, a phenomenon often referred to as the “Boriswave” after former Prime Minister Boris Johnson. The surge stems from post-Brexit immigration policies aimed at attracting high-skilled workers and their families, as well as large numbers of students, health workers, and humanitarian visa holders.

Johnson’s government implemented fast-track visa schemes to draw in "the brightest and the best," offering full labor market access to dependants. These policies have collectively contributed to an estimated net migration increase of at least 2.7 million people over the past five years. However, the impact of this influx on Britain’s economy, public services, and taxpayers remains a subject of debate.

A key factor in assessing the benefits of migration is the economic contribution of migrants compared with the cost they impose on the state. Most migrants arrive in their twenties or thirties, bypassing the years when state spending is highest on education and healthcare for children. This early arrival age gives them the potential to be net contributors through their working lives and into retirement.

Data indicate that European migrants tend to earn roughly £2,000 more annually than UK-born workers. Wages among non-European migrants vary substantially by nationality, with Nigerians averaging £35,000 per year, Indians £33,000, but Pakistani migrants earning around £25,000. While a relatively small proportion of visas—around 263,000—have gone to skilled workers, there have been substantial numbers of health and social care workers (296,000) and their dependants, as well as 2.4 million students and humanitarian visa holders, many of whom also contribute to the workforce, albeit in lower-paid roles.

The Migration Advisory Committee (MAC) has estimated the lifetime fiscal contribution of skilled workers earning an average of £75,000 to be around £689,000, rising to £931,000 for those who remain professionally active for most of their working life. Health and care workers generate a positive contribution of £54,000 on average, but their dependants impose a net cost of £67,000. Family visa holders, often partners with lower labor market participation, are estimated to have a net cost to the state of roughly £109,000 each. Humanitarian visa holders, including those granted asylum, are generally expected to have a negative fiscal impact, particularly because many settle long term on relatively low incomes.

Since 2021, the UK has granted asylum to about 200,000 people, whose long-term costs to public finances have been estimated at over £500,000 per individual. This figure substantially offsets gains from other types of migration, complicating the overall fiscal picture.

Overall, legal migration since 2021 appears to have generated a net economic benefit for the UK, with an estimated lifetime gain of around £130 billion when considering work-related and family visas (excluding students due to data uncertainties). However, the financial burden associated with asylum seekers during the same period is projected at about £110 billion, significantly dampening net gains.

In summary, while post-Brexit migration policies have succeeded in attracting skilled and productive workers, the broader migration mix, especially the inclusion of many dependants and asylum seekers, poses challenges for the UK’s public finances and raises questions about the long-term sustainability and balance of the current immigration system.