Mr Farage insisted the current law gives Commonwealth citizens the same voting rights as British nationals, provided they meet specific conditions.
The conditions, set out under the Representation of the People Act 1983, state that Commonwealth citizens qualify to vote if they have leave to remain or do not require leave.
The Reform UK leader warned that extending the franchise beyond British citizens undermines national sovereignty and leads to elections being fought on international issues.
Mr Farage’s claim followed reports of illegal family voting in the Gorton & Denton by-election, with police now investigating allegations that 12 per cent of voters were affected by the outlawed practice.
However, Mr Farage is also looking to limit access to postal voting to the elderly, the disabled, serving armed forces personnel, and those working overseas during an election.
The Reform UK leader previously warned about postal voting issues in 2019 when the Brexit Party narrowly missed out on winning a crunch parliamentary by-election in Peterborough.
Nigel Farage feels aggrieved by the result of Thursday’s Gorton & Denton by-election
Writing in today’s Sunday Telegraph and Mail on Sunday, Mr Farage said: “For too long, postal voting has allowed our elections to be turned into a laughing stock, riddled with fraud, intimidation and outright cheating. It’s been allowed to go on for years and has poisoned trust in our democracy.
“Meanwhile, allowing non-Brits – people with zero connection to this country – vote on our future is absurd. It is right that only British citizens should be able to vote in British parliamentary elections.
“That’s why a Reform Government will immediately ban wholesale postal voting and ensure only British citizens can vote in elections in order to bring back trust to British democracy.”
Postal voting was first introduced for people serving in the Armed Forces shortly after the First World War.
The Reform UK leader claimed 48 per cent of residents are foreign-born in Longsight
Following a series of extensions to civilians, Sir Tony Blair made the practice available to anyone who requested postal ballots in 2000.
However, Reform UK’s proposed change looks set to mirror France’s decision to outlaw the electoral practice in 1975.
Mr Farage is pushing for such changes amid mounting allegations of voter fraud and sectarianism in the Gorton & Denton by-election.
Green Party candidate Hannah Spencer saw off Reform UK’s Matthew Goodwin with a majority of 4,402 votes.
Meanwhile, Labour’s Angeliki Stogia failed to defend a majority of 13,413, falling behind both the Greens and Reform UK.
Green Party candidate Hannah Spencer won the by-election by more than 4,000 votes
However, the Green Party’s shock victory was marred by accusations of dirty campaigning after videos released in Urdu were described as “whipping up hatred” by including images of Benjamin Netanyahu and Narendra Modi.
Mr Farage is now suggesting Reform UK won in Gorton & Denton among British-born voters.
He added: “What happened last Thursday at the Gorton and Denton by-election, in which the Green Party emerged victorious in a historically Labour stronghold, was the most glaring example yet of what happens if we’re not careful about the impact of mass immigration and the legitimacy of those who can vote in our elections.”
The Reform UK leader claimed 10 per cent of the constituency was born in Pakistan, with the proportion of foreign-born residents jumping to 48 per cent in Longsight.
However, Mr Farage’s detractors have accused him of playing from Donald Trump’s 2020 playbook.
Reform UK is also looking to clamp down on postal votes
Mr Trump peddled unfounded claims that the 2020 US Presidential Election was rigged in favour of his Democratic challenger, Joe Biden.
A Green Party spokesman said: “This is an attempt to undermine the democratic result and is straight out of the Trump playbook.
“We’ve just won a historic by-election by a comfortable margin.
“We’ve shown the country that Greens can beat Reform, despite their big business donations.”