Mr Farage, 56, a former European Parliament member, said he is stepping back from active politics after 30 years of campaigning.
He tweeted: "I won't be involved in elected politics any longer, but I'm not going to go away from fighting the big battles of the day."
The former UK Independence Party and Brexit Party leader told The Sunday Telegraph: "This has taken away the better part of my adult life."
He added: "When you are an insurgent anti-establishment group, the people at the top have to raise the money, organise the discipline and do the whole thing, and I'm done."
He thinks he can continue to speak out about any big issues via social media.
His Brexit Party became known as Reform UK.
In the 2019 general election, the Brexit Party contested 275 seats and took 2% of votes but did not succeed in electing an MP.
Reporting by PA