London alone, as the British economy’s powerhouse, is home to 191,000 millionaires – more than the combined millionaire population of Wales, Scotland, Northern Ireland and Northern England – as those in the capital have reaped the benefits from owning the most expensive property in the country.

But according to the Barclays’ Prosperity Index – which combines a range of economic measures including employment rates and average earnings to calculate a score for each region of the UK based on how prosperous they were – plenty of others in the region are joining the millionaire ranks.

John Godfrey, a regional director of Barclays Wealth and Investment Management, said: “The 41% increase in the number of millionaires since 2010 has been driven by factors including a healthy financial services sector and a thriving entrepreneurial scene”.

“A number of big businesses, including well-known technology and pharmaceutical firms, have set up or moved to the area, which helps to drive further prosperity”.

Cambridge is singled out for its tech boom, accounting for numerous 32,570 business start-ups in the region, which is ranked in just seventh place for the ratio of business births to deaths.

“We must acknowledge that this prosperity is still not spread evenly across the UK, with some regions still recording high unemployment and insolvency rates”, Bhargava said.

One in 65 adults is now classed as being a millionaire because of booming house prices and gains on the stock market, according to new data from Barclays.

The South East received the second highest score in the index overall – again behind London – owing to its strong wages and house price growth.

Despite the jump in wealthy Britons over the past five years, the research said growth in millionaires was expected to return to more normal levels over the long term, with a 9% increase in the UK expected by 2025, in line with GDP growth.

The bank’s research found that every UK region is richer than it was five year ago. “We need to collectively support entrepreneurship and educational attainment in regions outside of London and the South East so that they continue to grow and prosper”.