Reform UK received £7m from two overseas British crypto billionaires earlier this year, figures show, helping it cement its fundraising lead in recent months.
Hong Kong-based businessman Ben Delo gave £4m to Nigel Farage's party, according to latest filings, whilst Christopher Harborne, who lives in Thailand, donated £3m.
The donations were made in the weeks before the government announced a £100,000 cap on donations after 25 March from British citizens living overseas.
The planned limit has sparked a row between the two parties, with Reform accusing Labour of "choking off legal funding for its main rival".
The donations were contained in the latest publication of large donations by the Electoral Commission, covering the first three months of this year.
The filings show Reform accepted £2m from Delo on 14 January, and £2m on 2 March, as well as £3m from Harborne on 23 January. None of the donations was made in cryptocurrency.
The donations accounted for the lion's share of the £9.3m in private donations declared by Reform during the period, and around a third of the £20.7m total declared by all parties.
The party also declared a further £1.1m in donations from biotech entrepreneur David Grainger.
Sheffield-born Delo, who co-founded BitMEX, a cryptocurrency trading platform, is a first-time donor to the party but had revealed the donations earlier this year.
Harborne, a British cryptocurrency investor, gave £12m in total to Reform in 2025, including a huge £9m donation in August, the largest ever single sum given by a living person to a British political party.
Farage is under investigation by the parliamentary standards commissioner over whether he should have declared a £5m cash gift he received from Harborne ahead of the 2024 election upon his election as an MP.
Farage argues he was under no obligation to register the "purely private" gift, as it was unrelated to his parliamentary or political activities.
The large donations from individuals meant Reform's fundraising efforts far outstripped those of both Labour and the Conservatives, who each declared around £4m in donations from private sources over the period.
It comes after Nigel Farage's party received more than £5.4m in large donations in the final three months of last year, more than any other, as parties sought to fill their coffers ahead of a crucial set of elections in May.
In the latest three-month period, Labour's biggest donations were £550,000 each from longstanding donor Lord David Sainsbury and Gary Lubner, the former boss of Autoglass, who gave millions to Labour ahead of the last general election.
The party also declared a total of £1.4m from seven different unions, including £392,544 from Unite and £366,936 from Unison.
By contrast, the Greens registered just £209,000 in private donations, with the Liberal Democrats declaring £2.2m.
Political parties are required to report all donations above £11,180 to the Electoral Commission. Its figures do not include smaller donations or income from membership fees, which appear separately in parties' annual accounts.
Opposition parties also receive public funds to support their parliamentary duties, with allocations based on their performance at the previous election.
In the first three months of this year, the Conservatives received £1.8m from this route, with the Lib Dems receiving £727,134 and Reform £98,763.
The latest filings come after the government announced a £100,000 annual cap on the amount that British citizens living outside the UK can donate to political parties.
It plans to apply the cap retrospectively from 25 March once legislation to create the cap has passed Parliament, with parties obliged to return any money over the limit received after this date.
Ministers say the move, announced alongside a government-commissioned review earlier this year, will reduce the risk that impermissible donations from foreign nationals will "slip through the net".
But it has prompted a furious row with Reform and its key donors, who have accused Labour of trying to stymie their party's progress ahead of the next general election, which must be held by 2029.
In April, Delo wrote that he planned to bring forward his plans to return to the UK so he could continue to "contribute more to Reform's budget".
Harborne, who has previously claimed he was "the reason" the Labour government introduced the cap, has said he could challenge the limit in court and has not ruled out returning to the UK to get around it.
