The annual boost - worth around a third in growth for the British economy - would continue for at least 12 years as Britain’s economy is transformed by throwing off the shackles imposed by Brussels.
It is the equivalent of adding the entire NHS and defence annual budgets back into the UK each year.
With France and Germany putting pressure on the UK to change its mind and Remainers attempting to force the UK to at least stay part of the Single Market under Brussels rule, Mr Longworth has released analysis on behalf of Leave Means Leave to show that Britain will be hugely better off even if talks break down.
He pointed out that just three measures; deregulation, the reinvesting the net UK contribution to the EU, and removing external tariffs to the rest of the world imposed by the EU, would amount to a 7.2 per cent boost to our economy, between £120 and £150 billion.
This is before extra boosts to the economy created by new free trade agreements being set up around the world.
Writing for the Daily Express online, he said: "This would be like increasing our economic growth rate by a third every year for twelve years! "
