George Cottrell reportedly transferred more than $2 million to his mother days before she donated money to Reform UK.
The party’s finances have come under media scrutiny over recent weeks, and the Metropolitan Police are looking at whether donors might have circumvented restrictions on the sources of political funding.
The Guardian newspaper reported that Mr Cottrell’s mother Fiona Cottrell received sums of cash, part of which made its way to the political party.
Ms Cottrell is thought to have received one deposit of $1.4 million and then two tranches of more than $300,000 each.
She allegedly told bankers the money came from her son, when she was asked about the deposits.
She received the money around 24-72 hours before she made a donation either to Reform UK directly or to the company Britain Means Business, according to The Guardian.
The Met’s investigation concerns donations to Reform UK from Britain Means Business, a fundraising vehicle whose director is the party’s deputy leader Richard Tice.
The Times previously reported that the firm gave Reform two donations of £250,000 in the run-up to the 2024 general election.
The money was paid to his company by Reform donor Ms Cottrell, Mr Tice has previously outlined.
Reports suggest she gave £1 million to Britain Means Business in June 2024, and half of that money was then given to Reform.
Mr Cottrell is a convicted criminal who provided funding for Nigel Farage’s security and staffing in the year before he was elected.
A Reform UK spokesman said: “Reform takes pride in its stringent vetting of donations and always ensures that the Electoral Commission guidelines on donations, as set out in the Political Parties, Elections and Referendums Act 2000, are strictly followed, as has been the case with all donations.”
Mr Tice has previously defended his links with the Cottrell family.
“My family have known the Cottrell family and the broader Hesketh family for 50 years,” he said.
“A very successful aristocratic family, and as far as I’m concerned, she’s a permissible donor and that’s the end of it.”
At the weekend, a Met spokesperson said: “An investigation was launched in February 2025 after a referral was made to the Metropolitan Police by the Electoral Commission relating to donations made to a political party ahead of the 2024 UK general election.
“Detectives from the Met’s Special Enquiry Team are investigating alleged offences under Section 61 of the Political Parties, Elections and Referendums Act 2000.
“Early investigative advice has been sought from the Crown Prosecution Service and two people have so far been interviewed under caution. No arrests have been made.
“An offence under this section is not one that the Electoral Commission can investigate and, as such, it is a matter for the police.”
Bridget Phillipson, the Labour Party chairwoman, urged Reform UK leaders to “stop ducking questions and come clean about who’s bankrolling the party”.