An Essex businessman who won government contracts paying his company £3.5m a day for transporting and accommodating asylum seekers has been named among the 350 richest people in the UK.

Graham King, the founder and majority owner of a business empire that includes Clearsprings Ready Homes, which won a 10-year Home Office contract for housing thousands of asylum seekers, was on Friday named alongside King Charles III, the prime minister and Sir Paul McCartney on the Sunday Times rich list of the wealthiest people.

King, 56, is estimated to have amassed a £750m fortune from “holiday parks, inheritance and housing asylum seekers for the government”. Clearsprings Ready Homes made £62.5m in profits after tax for the year ending January 2023, more than double its profits of £28m the previous year.

Ranked 221st, King is one of several new entries to the 2024 rich list alongside the Formula One driver Sir Lewis Hamilton and Tony and Cherie Blair’s son Euan, whose apprenticeship firm Multiverse is said to be worth £1.4bn. The newspaper estimated that Blair, 40, has built up a £375m fortune – far more than his father’s speculated £47m – making him the 337th-richest person in the country.

Blair has claimed that some young people turned down places at Oxford to join his scheme. His business, co-founded with his friend Sophie Adelman, offers what he claims is “a genuine, credible alternative that can compete with university”.

The Hinduja brothers retained the title of the UK’s richest people with an estimated fortune of £37.2bn, up from £35bn last year – and the largest fortune recorded in the newspaper’s 36 years of ranking the wealthy.

However, this year’s list reveals the largest fall in the number of billionaires – from 177 to 165 – in its history. “This year’s Sunday Times rich list suggests Britain’s billionaire boom has come to an end,” said Robert Watts, the compiler of the list. “Many of our homegrown entrepreneurs have seen their fortunes fall and some of the global super-rich who came here are moving away.”

Sir Jim Ratcliffe, the founder of the petrochemicals company Ineos, who this year bought a 27.7% stake in Manchester United, is named as the biggest loser on the list, with a £6.2bn decline in his fortune to £29.7bn.

The richest 350 individuals and families together hold a combined wealth of £795bn – a sum larger than the annual GDP of Poland.

Meanwhile the personal fortune of Rishi Sunak and his wife, Akshata Murty, has increased by £120m to an estimated £651m in the run-up to the next general election, the list reveals.

Priya Sahni-Nicholas, a co-executive director of the Equality Trust, a charity that campaigns for the creation of a fairer society, said the list “demonstrates the obscene extent of inequality” in the UK.

“Billionaire wealth is up by more than 1,000% since 1990 at a very real cost to us all,” she said. “This rich list is built off record bill increases, massive price hikes for essentials, an endless shortage of decent homes, and huge investment in fossil fuels.

“To make progress on these crises we must tackle inequality. The super-rich have spent centuries diverting wealth into their hands, making our democracy less responsive to people’s needs and damaging our communities. The result is we are poorer, sicker, less productive, unhappier, more polarised, and less trusting.”

Luke Hildyard, the executive director of the High Pay Centre, a thinktank focused on pay, corporate governance and responsible business, said: “The rich list always prompts intense interest in billionaire rivalry over who’s up and who’s down, but as a society we should also ask whether this represents a fair, proportionate or efficient allocation of resources.

“Twelve of the top 20 rich-list entrants inherited their wealth or business. They all depend on the workers at the companies they own and invest in, or the public services and infrastructure that enable the economy to function.

“Allowing such a tiny number of people to capture such a huge share of collectively created wealth is not an inevitability but a policy choice that needs to be properly debated.”

Researchers at the University of Greenwich worked out that the wealth of the 200 richest families has ballooned from £42bn to £711bn since the rich list began 36 years ago, while the overall public wealth of the country has fallen from £337bn to a shared debt of £1tn.

Ben Tippet, a lecturer in economics at the University of Greenwich, said: “When the rich list was first published in 1989, The queen sat at the top of the list. Today, the king has been pushed down to 258th place, as business owners, aristocrats, celebrities, and others have accumulated vast and unimaginable fortunes.

“During this time, the wealthiest 200 people have seen their wealth grow on average by 5.2% per year in real terms, compared to just 1.6% for GDP. As the economy continues to stagnate and the UK government accumulates more debts than assets, we need to remember that the UK does have a growth model – it’s just for the super rich.”

Sunday Times rich list 2024: top 20

1 Gopi Hinduja and family £37.196bn (industry and finance: Hinduja Group).

2 Sir Leonard Blavatnik £29.246bn (Investment, music and media: Access Industries).

3 David and Simon Reuben and family £24.977bn (Property and internet: Reuben Brothers).

4 Sir Jim Ratcliffe £23.519bn (Chemicals: Ineos Group).

5 Sir James Dyson and family £20.8bn (Technology: Dyson Group).

6 Idan Ofer £14.96bn (Shipping and industry: Israel Corp).

7 Lakshmi Mittal and family £14.921bn (Steel: ArcelorMittal).

8 Guy, George, Alannah and Galen Weston Jr and family £14.493bn (Retail: Primark).

9 John Fredriksen and family £12.867bn (Shipping and oil services).

10 Kirsten and Jorn Rausing £12.634bn (Inheritance and investment: Tetra Laval).

11 Alex Gerko £12.055bn (Finance: XTX Markets).

12 Michael Platt £12bn (Hedge fund: BlueCrest Capital Management).

13 Charlene de Carvalho-Heineken and Michel de Carvalho £11.751bn (Inheritance, brewing and banking: Heineken).

14 The Duke of Westminster and the Grosvenor family £10.127bn (Property: Grosvenor Group).

15 Barnaby and Merlin Swire and family £9.9bn (Industry, transport and property: Swire Group).

16 Marit, Lisbet, Sigrid and Hans Rausing £9.188bn (Inheritance: Tetra Laval).

17 Carrie and François Perrodo and family £9.168bn (Oil, gas and wine: Perenco).

18 Nicky Oppenheimer and family £7.937bn (Diamonds and mining: De Beers).

19 Lord Bamford and family £7.65bn (Construction equipment: JCB).

20 Denise, John and Peter Coates £7.467bn (Gambling: Bet365).

• This article was amended on 24 and 31 May 2024. The richest people in Britain have seen their wealth grow, in real terms, by an annual average of 5.2% since 1989, not 15% as an earlier version said, owing to incorrect figures provided to us; meanwhile the average annual GDP growth over the same period was 1.6%, not 2%. Incorrect information also meant that Barnaby and Merlin Swire and family were originally placed in sixth position with a net worth of £17.2bn, instead of the correct position of 15th with £9.9bn.