Net migration to the United Kingdom has nearly halved over the past year to 431,000, according to new data from the Office of National Statistics (ONS).

The drop from 860,000 in the year to December 2024 will help to defuse a heated debate over immigration in the UK.

The data represents the biggest calendar-year drop since the early stages of the COVID pandemic, when net migration fell from 184,000 in the year ending December 2019 to 93,000 in the year ending December 2020.

It is also the largest net drop for any 12-month period, the ONS said.

The agency said the sharp decline was caused by reduced immigration from non-EU countries for work and study visas and by an increase in emigration from the UK.

The development follows a series of policies implemented by the last Conservative government that have been continued by the current Labour government.

The issue of net migration has become a key electoral battleground, with deepening concern among voters about the NHS, housing and the small boats crisis in the English Channel.

With the challenge from Nigel Farage’s Reform UK focused on immigration, the figures will be claimed as a boost to Prime Minister Keir Starmer, who has pledged to reduce them before the next election.

The fall in numbers has also been caused by a series of restrictions introduced by the Conservative government in the year before July’s general election.

The government pledged to bring down levels of immigration during last year’s general election campaign and will point to these statistics as evidence that they are delivering.

Home Secretary Yvette Cooper said the fall was “important” and that the recently released White Paper sets out “radical reforms” that will bring the number down further.

Separate figures released by the Home Office show 109,000 claimed asylum in a year to March 2025 – a slightly different period to the ONS’s – but an increase of 17 per cent on last year.

If current trends continue, net migration is projected to level out at around 300,000 people a year.

Though that is somewhat higher than before Brexit, many economists say Britain could comfortably absorb it, saying that high levels of immigration have been wrongly blamed for other policy failures, like chronic underinvestment in public services or sluggish economic growth.

Dr Madeleine Sumption, Director of the Migration Observatory at the University of Oxford, said: “This record-breaking decline in net migration was possible primarily because numbers had previously been so high. UK migration patterns in 2023 were very unusual, with unexpectedly large numbers of visas for care workers, international students, and their family members. This made it easier for the government at that time to bring down the numbers.

“The economic impact of this decline is actually likely to be relatively small. That’s because the groups that have driven the decline, such as study and work dependants, are neither the highest skilled, highest-paid migrants who make substantial contributions to tax revenues, nor the most disadvantaged groups that require substantial support,” she said.

Recently, the British government has been in talks with third countries, including Albania, about deals to send them migrants who have been refused the right to stay in Britain and run out of legal options to avoid deportation.

Also, new rules mean migrants will wait longer to qualify for permanent settlement in the UK and will apply to people already in the country.

The government recently announced immigrants would now typically have to live in the UK for 10 years before applying for the right to stay here indefinitely – double the current five-year period.

It is not clear whether this applies to the approximately 1.5 million foreign workers who have moved to the UK since 2020.