United Kingdom citizenship applications from United States citizens hit record levels in 2024, driven by concerns over US President Donald Trump's then potential return to power and changes to British tax laws.

Applications from US citizens reached 6,100 last year, a 26 percent increase from 2023 and the highest level for two decades of record-keeping, the Financial Times newspaper reported.

Total UK citizenship requests also hit a new high of 251,000, up 6 percent, according to the latest data sets published by the UK government last week.

In the final quarter of 2024, applications from US citizens jumped 40 percent, to around 1,700, compared with the same period a year earlier.

The increase stems from Trump's November election win and UK tax changes affecting departing US citizens, immigration lawyers said.

Elena Hinchin, partner at law firm Farrer and Co, called the US political climate "a very serious driver" of growing UK residency demands.

"We've definitely seen more interest in citizenship from the US since the lead-up to the election campaign," she said. "There's much more interest than under the previous Trump administration."

Changes to the UK's non-dom tax rules are prompting wealthy US residents to obtain citizenship before leaving, said Hinchin.

"Many high-net-worth individuals are considering leaving the UK given the tax changes," she noted. "They want to apply for citizenship now so that they don't lose the right to do so … it just keeps the door open and means more flexibility for their children."

UK citizenship requires applicants meet several requirements, including residency duration, British parentage, or marriage to a UK citizen. Applications from US citizens have shown consistent growth since late 2022, according to Home Office figures.

While US citizens became "particularly keen" on UK citizenship last year, motivations can involve multiple personal factors, according to Madeleine Sumption from Oxford University's Migration Observatory.

"For people moving from safe countries, politics tends to be a third or fourth order factor, not a key reason for moving on its own," she told the FT.

A "huge spike" in British citizenship searches followed the US November election, said Ono Okeregha, a director at Immigration Advice Service, who described the rising number of applications as the "aftermath of the first Donald Dash", when US citizens who fled Trump's 2016-2020 presidency became eligible for UK citizenship.

Ireland's government also reported a significant jump in US citizens seeking citizenship in Ireland.

Applications from US residents for Irish citizenship through Foreign Birth Registration, or FBR, which is the process for claiming citizenship through Irish ancestry, surged to 11,601 in 2024, up from 7,726 in 2023, accounting for more than a quarter of all FBR applications worldwide, RTE News reported last month.