Tens of thousands of anti-EU activists will distribute more than one million leaflets across the UK when they hit the streets on 5 March, Grassroots Out (GO) has claimed.
The Brexit campaign told IBTimes UK that the drive is going to be the "biggest single co-ordinated" action day in British referenda history.
John Flack, deputy campaign chief for GO, estimated that his activists will man more than 350 identical street stalls on the day.
"They will be getting out our message as to why Britain will be much better outside the EU," he said.
"There will be tens of thousands of activists out and we are looking to distribute in excess of one million leaflets just on Saturday alone."
The Eurosceptic campaigners will be spreading their anti-EU message in David Cameron's consistency of Witney, but the prime minister's seat has not been highlighted as a specific target for GO.
"The stall in Whitney will be the same as the hundreds in high streets and market places throughout the UK," Flack explained.
He added: "There are other people doing the clever social media bit and the online campaigning and the big set-piece rallies.
"We are about good old-fashioned traditional grass-roots campaigning – engaging face-to-face with the voters."
Flack, a self-described "old war horse" who has stood for the Conservatives at European Parliamentary Elections, stressed that party politics did not have a place in GO's campaign.
"The whole thing about GO is that we take off our party political hats, we take off our preconceptions with each other, we take off our party colours, but we are all unified to get Britain out of the EU," he argued.
The three Brexit campaigns
GO was formed by Labour MP Kate Hoey and two Tory MPs Peter Bone and Tom Pursglove in reaction to the in-fighting between Vote Leave and Leave.EU.
The group initially said it would not compete for the Electoral Commission's official Brexit campaign designation ahead of the 23 June vote.
But the umbrella GO Movement group was later created to challenge Vote Leave, which enjoys the support of cabinet ministers such as Justice Secretary Michael Gove, for the £600,000 ($846,705) grant and £7m spending cap from the Electoral Commission.
Nigel Farage and Ukip's National Executive threw their support behind GO for the nomination and Leave.EU, which was co-founded by Ukip donor Arron Banks, has announced its support for GO.
The campaign caused controversy when it unveiled Respect leader and Eurosceptic George Galloway as a "special guest" at a rally in Westminster.
Tens of attendees rushed for the exit – some in disgust, some hoping to get home – when the left-winger took to the stage.
One disgruntled man told IBTimes UK that the decision to invite Galloway to the event was a "f***ing disgrace".
More controversy came when Ukip's former deputy chairman Suzanne Evans was axed from her post.
The move came after Evans told IBTimes UK that she would be sticking with Vote Leave, alongside Ukip's only MP Douglas Carswell, despite her party's ruling body backing GO.
But a Ukip source described the decision as a "shuffling of the decks" prior to May elections and the EU referendum.
Vote Leave, which is run by Gove's former special adviser Dominic Cummings and lobbyist Matthew Elliot, will launch its own mass day of action on 12 March. The Take Control Day will involve hundreds of events across the UK.
A spokesman for Britain Stronger In Europe, the main pro-EU campaign, said the group is regularly organising hundreds of events across the country on the weekends leading up to the referendum.