After weeks of facing accusations he had failed to properly declare millions of pounds worth of gifts from wealthy backers, Farage used a televised announcement on Tuesday to vent his anger over what he described as a "pile on" by Britain's liberal elite.
"I've decided that the people of Clacton should be the judges of my actions," he said, announcing his decision to step down only to trigger an election in the southern English area where he was elected to parliament for the first time in 2024.
"This will be a people versus the establishment by-election" he said. "It is a chance to stick two fingers up to the entire establishment."
Over the last few weeks, Farage, 62, had become visibly angry over questions on both his personal finances and those of his party, which has led in almost every opinion poll for more than a year.
He is being investigated by parliament's standards watchdog over a five million pound ($A9.6 million) gift from a billionaire crypto investor who his critics say was not properly disclosed. It has yet to rule on the case.
He also said the standards watchdog had opened another investigation over a report of separate donations from a former aide, who was once convicted in the US for wire fraud.
Farage has denied any impropriety in his financial dealings, but after staging almost weekly press conferences, his appearances in public have dwindled of late and in recent days he has complained about reporters harassing his family.
In a speech when the usually composed Farage stumbled on some of his words, he said he had needed additional funds from supporters to pay for personal security and that he had given up a well-paid job decades ago to fight for the Brexit cause he believed in.
It was a long way from his usual media appearances, where the man who is often credited with forcing a referendum on whether Britain should stay in the European Union revelled in castigating his opponents with often colourful language.
He said the "final straw" had come when he accused journalists of intruding into his daughter's privacy despite her never being engaged in politics.
He said Sky News had contacted his family. Sky News said in a statement: "We approached the property off-camera on a single occasion, identified ourselves, and the occupant chose not to engage."
Farage said he would not tolerate intimidation of his family. "So yes, you can ask, am I angry? Well I've never been angrier in my life." He repeated: "I've done nothing wrong."
It is a risky move but one that has characterised Farage's political career. He had supposedly retired from politics when he stood down as leader of one anti-EU party in 2016, shortly after the Brexit vote, only to return two years later.
By framing the so-called by-election as the people versus the establishment, he can test out a strategy before a national election due in 2029 to paint the governing Labour Party and Conservatives as the elite, with him and Reform as the underdog, a source close to Reform said on condition of anonymity.
"I will fight to win," he said.
"I will fight to continue the political revolution that Reform has started."
