Nigel Farage has said he "paid a lot of money to make sure we have done everything right" regarding the purchase of a home in his Clacton constituency.
The Reform UK leader told broadcasters he had a "very expensive week" seeking advice from tax experts as he faced questions over the Clacton property.
The Clacton MP said he had consulted a KC to ensure "the right amount of council tax has been paid".
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"I have done everything I can to prove everything I have done has been legal and correct," he said.
Mr Farage's lawyers, Grosvenor Law, said in a statement they had received written advice from a KC that "concludes that there is no underpayment of SDLT (stamp duty land tax), that SDLT paid was properly calculated and that there is no basis to suggest there has been any improper avoidance or evasion of tax in respect of the purchase".
Reform UK's leader has been under scrutiny after he criticised former deputy prime minister Angela Rayner for failing to pay enough stamp duty on her home in Hove, East Sussex.
Last November, Mr Farage told Sky News he "just exchanged contracts on the house. I've bought a house in Clacton".
The Daily Mirror later reported that it was his partner who bought the house, and in doing so, only paid standard stamp duty as it is her main home.
Had Mr Farage bought the house, he would have been liable for an additional £44,000 in tax as a second home purchase.
However, it would not be illegal for Mr Farage to gift or transfer money to his partner for her to buy a property in her own name and pay the lower rate of stamp duty.
Mr Farage denies doing this, saying instead that his partner Laure Ferrari was able to purchase the property herself using family wealth.
Pressed on whether any of his own money was used to buy the house, the Reform leader said: "No, no, no, no. Listen, can I be clear about this? The money was legally hers.
"The estate agent and everyone did the 'know your customer rule checks' it was her legal money. She bought the house. The deeds are in her name. Council taxes in her name. I don't have any financial stake in it whatsoever other than she lets me stay there. But then, given that I'm a partner, that's not really that unusual."
He added: "I have given every answer to this I want to give. I've even been this week to a King's Council tax expert, and paid a lot of money to make sure that everything we've done is legal and right, and, crucially, that the right amount of council tax has been paid."
Asked why he sought legal advice if he had no part in buying the house, he said: "Because I was really concerned about what was being said by some elements of the press."
Ms Rayner resigned as deputy prime minister and housing secretary last week after admitting she did not pay enough tax on her second home. She also quit as deputy leader of the Labour Party, an elected post.
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Ms Rayner admitted to Sky News' political editor Beth Rigby on the Electoral Dysfunction podcast on Wednesday that she should have paid the higher rate of stamp duty on a home she bought in Hove, East Sussex, as it was her second property.
After referring herself to Sir Laurie Magnus, the prime minister's independent ethics adviser, she resigned after he found she had breached the ministerial code.
Following her resignation, Mr Farage said her not paying enough stamp duty "screams to entitlement".
"It screams to a government that, despite all the promises that this would be a new, different kind of politics is as bad, if not worse, than the one that went before," he added.
A race to replace Ms Rayner as Labour's deputy leader is now under way.
The two candidates who face a vote of the membership are Education Secretary Bridget Phillipson and former Commons leader Lucy Powell.
(c) Sky News 2025: Farage has 'expensive week' seeking tax advice in row over Clacton home