Farage, who is also the MP for Clacton in Essex, said he believed his party would “win many, many seats” in the South East, adding that Surrey and Sussex residents had been “denied” an opportunity to vote in local elections.
Elections in Sussex were set to be postponed in 2026 but the government reversed the decision after a legal challenge by Reform.
The party hopes to make significant gains in the county.
Reform UK also revealed two defectors from the Conservatives on Wealden District Council, David Greaves and Neil Cleaver.
BBC South East will be speaking to all the main political parties before 7 May.