With combined wealth up nearly 10 per cent, and now three billionaires in the county, here’s how the wealthiest 50 with strong links to Herts are making their ideas and skills pay.

Clockhouse Nursery are delighted to sponsor the Hertfordshire Life Richest 50 Feature. It's fantastic for us to be able to support the incredible success that is enjoyed by some of the leading businesses and individuals throughout Hertfordshire.

We have been providing quality plants at reasonable prices since 1928 and our ethos is simply, we supply just plants and what you need to grow them with no unnecessary distractions.

We are very proud to say that although the appearance of the site is constantly changing, nothing fundamentally has, we like to think the nursery is still unique in that, as far as possible plants of the highest quality are produced on site to sell direct to the public at our lowest possible prices.

Clockhouse Nursery offers a comprehensive range of top quality plants, seeds and bulbs, composts and garden sundries and we value our customers very highly. So whether you're a professional gardener, a dedicated amateur or simply one for weekend pottering, you will always be welcome, where you will find all the essential requirements for a great garden.

Come along and meet the garden gang at Clockhouse Nursery, Forty Hill, Enfield, Middlesex, EN2 9EU. Call us on Tel: 0208 363 1016

You can also follow them on Facebook | Twitter | Instagram | LinkedIn

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1. Mike Ashley

DOB: 09/12/64 Industry: Sports equipment & fashion

2020: £2.715bn 2019: £2.010bn

The billionaire who once sparked anger from staff after he emptied out a wad of £50 notes during a security check on a PR tour of one of his warehouses said he wants to create 50 millionaires with a new staff bonus scheme. Ashley, who owns Sports Direct and House of Fraser, says that hundreds of staff would receive payouts of £100,000 each under the proposed plans. Approval for the £100m scheme will be needed from the tycoon's fellow shareholders, and Ashley has made clear he will not benefit from the scheme personally. But after a stellar year for his retail empire's share price the 55-year-old retailer can probably live without another bonus. Over the past 12 months the stock market value of Frasers Group - the new name for Sports Direct - has soared from £1.4bn to £2.540bn. His 63 per cent stake in the business is now worth £1.602bn, up £705m in a year.

This former squash coach started Sports Direct in 1982 with a £10,000 loan from his parents. He pocketed £929m in one day when he floated Sports Direct on the stock market in 2007, and another £314m from further share sales in 2014 and 2015. In December 2016 Sports Direct successfully agreed a sale of Dunlop to Japanese buyers for £112m. His other windfalls include the sale of leases he owned on 32 Sports Direct stores, which raised nearly £87m. The Hertfordshire-based billionaire has bought up a string of struggling retailers in recent years, including Evans Cycles and Sofa.com. He has also become a vocal supporter of the high street, calling on the government to reform the business rates system to ensure internet traders pay similar levels of tax to bricks and mortar stores. The 80 per cent rise of his retail empire's share price over the past 12 months leads us to raise Ashley to £2.715bn this year.

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2. Sir Cameron Mackintosh

DOB: 17/10/46 Industry: Entertainment

2020: £1.28bn 2019: £1.18bn

Mackintosh has spent a staggering £220m on restoring and refurbishing his collection of London theatres in recent years. Sprucing up his Victoria Palace Theatre ahead of the West End launch of the hip-hop musical Hamilton set him back no less than £61m. But thanks to his skills as a producer of Les Miserables, Phantom of the Opera, Mary Poppins, Miss Saigon and countless other hit shows, these are costs that he can easily meet.

Indeed, profits at Mackintosh's main company almost tripled to £51.4m on record turnover of nearly £210m in 2018-19. A former stagehand at the Theatre Royal in London's Drury Lane, Mackintosh was raised in Cuffley, near Welwyn. He later graduated to stage manager on several touring productions, becoming a London-based producer in the 1970s. His big break came in 1981 when he produced Cats by Andrew Lloyd Webber. The show became the hit of the season and later one of the longest-running musicals on both sides of the Atlantic. We now value Mackintosh's business empire at £1.1bn - a figure also justified by his fast-growing theatrical rights business and the increase in value of his West End theatres. Private assets and a £35m dividend in 2015-16 take Mackintosh to £1.28bn.

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3. Peter Harris & family

DOB: 25/03/34 Industry: Hotels & caravan parks

2020: £1bn 2019: £965m

Harris has now joined the ranks of Britain's billionaires. He is best known for Bourne Leisure, which he founded in 1964 with David Allen. Every year more than four million families visit a Butlin's, Warner Leisure or another holiday destination owned by the Hemel Hempstead-based group. Profits fell back slightly to £153.4m on sales of nearly £1.1bn in 2018. The company's assets grew to more than £437.1m. Bourne should now easily be worth £1.5bn, raising the value of the Harris family's 42.9 per cent stake to £643.5m, up £43.5m in a year. Dividends of £60.5m were paid in 2017, on top of more than £210m in the four previous years.

Harris and his family also own 72 per cent of the £350m spread-betting operation Spreadex, which has paid out more than £106m in dividends over the past six years. A successful horse owner and trainer, Harris has substantial racing assets too. Taking account of strong dividends, past salaries, tax and other interests such as a private doctors' company and an aviation firm we put Harris and his family at £1bn.

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4. Luke & Brian Comer

DOB: 30/11/57 & 06/01/60 Industry: Property

2020: £880m 2019: £800m

The Comer brothers have presided over an array of successful property developments over the years. These include Royal Connaught Park, a former private school that served as Hogwarts in the Harry Potter films. The brothers, originally from Galway, have transformed the Hertfordshire site, creating 380 luxury homes priced at up to £2.8m.

The Comer brothers have come a long way since starting out in business together as plasterers in 1971. The siblings initially built a British property portfolio, and then went into the German market buying assets cheaply during a downturn. In 2010, with the Irish economy in deep trouble and property prices in freefall, they turned their attention to their homeland. The Comers once said that they had 500 companies worldwide, with assets worth £2.25bn. 'A conservative evaluation would be we'd be worth around £1bn in England, three-quarters of that in Germany and half a billion in Ireland,' Luke once told an Irish newspaper.

We can see nearly £106.2m net assets in 15 British Comer companies. Luke lives quietly in Monaco while Brian has a residence in Hertfordshire complete with its own golf course. We raise the Comers to £880m this year.

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5. Tim Martin

DOB: 28/04/55 Industry: Pubs

2020: £573m 2019: £420m

Brexit-backing pub chief Martin will be raising a glass to Britain's departure from the EU. He began withdrawing European drinks such as Jagermeister and Staropramen 18 months ago, instead offering produce from the USA, Australia, Chile, New Zealand, Argentina or the UK.

Anyone craving a Jägerbomb is now offered a Brexitbomb - a similar tipple made with the Lancashire-made spirit Strika. After starting out with Martin's Free House in London's Muswell Hill in 1973, this former surf bum has built up a chain of 900 pubs. The Watford-based JD Wetherspoon's sales rose to £1.8bn in the year to July 2019 and its shares climbed strongly after the Tory victory in the December general election. The group is now worth £1.68bn. The value of Martin's stake has risen to £540.3m, up £150.3m in 12 months. Dividends and other assets add another £33m after tax.

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6. Charles Gallagher and family

DOB: 15/10/59 Industry: Construction

2020: £510m 2019: £482m

Gallagher's father founded the Dublin-based house building group Abbey, which is now worth £268m on the stock market. He joined the board in 1986 and took over the chairmanship when his father died in 1993. Gallagher has increased his family's holding in the company to nearly 82 per cent, a stake currently worth nearly £200m, up £15m from a year ago.

The family's other main operation is Matthew Homes, based in St Albans, which made nearly £12m profit on £66.6m sales in 2017-18. With £116.8m net assets, it is still a £140m operation. The family's property operation, Gallagher Holdings, also showed £100.9m net assets and paid a £3.1m dividend in 2017-18. There is another £65.6m in a plant hire company in 2017-18, up £6.9m in a year. With some overlapping shareholdings, the Gallagher family should now be worth £510m.

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7. Tony Tabatznik & family

DOB: 02/08/47 Industry: Pharmaceuticals & film

2020: £500m 2019: £500m

South African-born Tabatznik made a fortune from selling Arrow Generics for $1.75bn to a US drug company in 2009. Tabatznik had founded the Stevenage-based pharmaceuticals company nine years before the deal, growing Arrow quickly into a leading manufacturer of tablets, capsules, creams, ointments and other products.

He had previously sold his family's Stevenage-based Generics (UK) operation to Merck, the German pharma giant. That deal in the mid-1990s netted £200m for him and his family stake. Since the Arrow sale Tabatznik has established a foundation that finances film makers, lawyers and activists seeking to deliver social change. He has also invested in the Bafta-winning Curzon cinema chain. Tabatznik and his family should still be worth at least £500m.

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8. Iris Gibbor & family

DOB: 29/08/51 Industry: Industry and Hotels

2020: £449m 2019: £422m

Gibbor chairs CP Holdings, the Watford-based conglomerate set up in the 1950s by her Austrian father Sir Bernard Schreier. He died in 2013 at the age of 95. Over the years the group has diversified into civil engineering, property development and serviced offices. The latest acquisitions include a controlling stake in an Athens-based construction machinery business. The group also includes Danubius Hotels, which has more than 50 premises in Hungary, Slovakia, Romania, the Czech Republic and Britain.

During 2018 CP's net assets rose to £420.7m, up £25.4m in a year. We add £28m to Gibbor and her family for past dividends and other wealth. Gibbor spent eight years working for the Australian TV company ABC News as a facilities manager before taking on her family's business.

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9. Sir Peter Ogden

DOB: 26/05/47 Industry: Computers

2020: £445m 2019: £338m

Ogden made his fortune from co-founding and building up the IT giant Computacenter. He set up the Hatfield-based operation with Sir Philip Hulme, who he studied with at Harvard. Computacenter floated on the stock market in 1998 and is now worth £1.9bn. He owns 18.7m shares worth around £316.5m - up £104.5m. He also had a £100m stake in Dealogic, a software company taken over in a £440m deal back in 2014.

Ogden also owns 25 per cent of MotorSport Vision (MSV) which runs the Donnington Park race track, Brands Hatch, Oulton Park, Snetterton and Cadwell Park as well as Bedford Autodrome. The operation made £5.4m of profits on turnover of £49.3m sales in 2018. With £27.6m of net assets MSV should still be worth £50m, with Ogden's 25 per cent stake valued at £12.5m. With dividends, a property in Sandbanks, and after his hefty charitable work - which earned him a knighthood in 2005 - Ogden is worth £445m.

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10. Colin Allen & family

DOB: 03/05/60 Industry: Caravan parks & hotels

2020: £390m 2019: £360m

The late David Allen co-founded Bourne Leisure, the holiday camp and caravan park group, in 1964. The Hemel Hempstead-based group today owns Butlin's holiday camps. Profits fell slightly to £153.4m on sales of almost £1.1bn in 2018. The company's assets grew to more than £497.3m. Dividends of more than £60.5m were paid in 2018, on top of more than £210m in the four previous years. Bourne should now easily be worth £1.5bn, putting the Allen family stake to over £320m. Other family assets include a £30m holding in the spread betting firm Spreadex.

A profitable tree business and hefty Bourne dividends in recent years take the Allen family - now led by David's son Colin - to £390m.

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11. Tim Steiner & family

DOB: 09/12/69 Indsutry: Retailing

2020: £390m 2019: £300m

Former Goldman Sachs banker Steiner had the idea for setting up Ocado after reading about a grocery delivery service that went bankrupt in the United States. He believed the idea could take off in the UK, and launched the Hemel Hempstead-based company in 2000 with two ex-Goldman colleagues. Ocado floated on the stock market in 2010 with a value of £937m. Today the business is worth £8.9bn. Steiner and his trust Linc offloaded shares worth £127m in three tranches in the year leading up to November 2018. He still owns 23.6m shares in the business - a holding worth £297.2m.

We put Steiner conservatively at £390m due to a 2016 divorce settlement after the middle-aged executive began a relationship with a Polish lingerie model nearly 20 years his junior.

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12. Michael & Xochi Birch

DOB: 07/07/70 & 11/01/72 Industry: Internet

2020: £375m 2019: £375m

Bebo founder Birch and his wife Xochi have spent three years renovating the Devon pub he used to visit with his grandmother. The thatched roof at the Farmer's Arms in Woolsery, North Devon, had fallen in and the entire building was in need of a refresh after years of neglect. The project was completed  last year and the Birches - who had already saved the village's chippy - are now turning their attention to transforming the manor house into a hotel.

The Cheshunt-raised internet entrepreneur started the Bebo social networking site with his wife in 2005. Three years later they sold it to AOL for £510m, netting around £357m for their 70 per cent stake. They bought back Bebo for around £600,000 in July 2013, just five years after selling it. Now based in San Francisco, the couple also own The Battery, an exclusive private club and workspace for Silicon Valley's elite. The venue has restaurants, libraries and a collection of bars, including a secret one accessed from behind a bookcase after the member has moved a statue. We still value the couple at £375m after tax.

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13. David & Victoria Beckham

DOB: 02/05/75 & 17/04/74 Industry: Football & fashion

2020: £357m 2018: £350m

All is not well with Victoria Beckham's fashion label. The former Spice Girl's business racked up a £12.3m loss in 2018, with turnover falling to its lowest level for five years. The designer has been told she can no longer employ a chauffeur to ferry herself to work and has even offered to take a pay cut to help her ailing label. Fortunately, her other half's earning power remains strong. In the same year David's part of the Beckham business empire made a profit of £14.8m. Since stepping off the playing field the former England football captain has earned well from an array of advertising and endorsements for brands such as Pepsi, Samsung, H&M, Haig and adidas. These deals have been cannily structured to ensure that Beckham gets a cut of rising sales, rather than just a flat fee. His US football team Club Inter Miami is due to play its first game in March. That venture could become a game changer for the Beckhams' finances.

The couple's main holdings company, which encompasses almost all of their commercial interests, paid the couple a dividend of £11.7m in 2018. That payment leads us to raise Posh and Becks to £357m this year.

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14. Marquess of Salisbury, Robert Gascoyne-Cecil

DOB: 30/09/46 Industry: Property & art

2020: £345m 2019: £343m

The Marquess of Salisbury's family have called Hatfield House home for more than 400 years. The Jacobean mansion has provided the backdrop for an array of box office hits in recent years, including The Favourite, The King's Speech and the Paddington films. The house's walls are adorned with artwork believed to be worth at least £150m. The Marquess also owns Dorset's Cranborne Manor, parts of which date back to the 12th century. These two estates have some 10,300 acres in all.

His company, Gascoyne Cecil Estates, owns, lets and manages up to 300 residential properties in Hatfield, London and Dorset. There are plans to build hundreds of houses near Hatfield on the Marquess' land in coming years. The family also have a London estate with valuable acreage around Leicester Square. There are also assets in America. In all the Marquess and his family should still be worth around £345m.

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15. Charles Wilson

DOB: 24/07/65 Industry: Retailing

2020: £302m 2019: £280m

Wilson acquired the nickname 'three brains' during his time running UK food wholesale giant Booker. When he arrived in 2005, sales were falling and the company was struggling with high debt. Wilson is largely credited with turning the business into a success story with a market cap of well over £4bn. This was not his first successful corporate revitalisation. Wilson had previously breathed life into Sir Philip Green's Arcadia group in 2002 - making £10m for himself in the process. In 2018 Wilson oversaw the £3.9bn merger of Booker with Tesco. He now has a stake worth £264.1m in the supermarket giant, up £20m on a year ago. These shares should have garnered Booker dividends of around £4m over the past year. Just a few months after the Booker-Tesco tie-up was completed Wilson stepped down after being diagnosed with throat cancer.

The rising value of his Tesco stake, past earnings and dividends, justify raising Wilson to £302m.

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16. Sir Philip Hulme

DOB: 27/08/48 Industry: Computers

2020: £300m 2019: £200m

Computacenter builds IT systems for clients across Europe, South Africa, the Americas and Asia. Hulme co-founded the Hatfield-based operation in 1981 after completing an MBA at Harvard Business School, teaming up with his course mate Sir Peter Ogden. Over the years Computacenter has worked for BMW, Royal Mail, Nationwide, Heathrow Airport and many other large private and public sector clients. The IT giant floated on the stock market in 2000 and is now worth more than £1.9bn.

These days Hulme serves as a non-executive director and still owns 16.12 per cent of the business. This stake is now worth £306.3m — rising strongly over the past year. Hulme also had a £100m stake in software company Dealogic, which was taken over in a £440m deal in 2014. Taking account of dividends and charitable donations, Hulme should be worth around £300m. 

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17. Peter Harris

DOB: 21/02/55 Industry: Retailing

2020: £193m 2019: £120m

Harris and his business partner Angus Thirwell have built Hotel Chocolat into one of the few new British high street success stories of recent times. The pair initially began selling mints, before moving into confectionary with Chocolate Express - initially growing a mail order business until launching their first Hotel Chocolat store in Watford in 2003. Harris, who initially met Thirlwell in the 1980s when he interviewed the young university dropout for a sales job at a Cambridge tech firm, concentrates on the finance and development side of Hotel Chocolat.

The pair made about £20m each when the retailer floated on the stock market in 2016. Harris still owns 31.5 per cent of the shares in the £550m retailer. His stake is now worth £173m - up £72m since our last look. Taking account of tax, dividends and other wealth should take Harris to £193m.

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18. Angus Thirlwell

DOB: 17/04/63 Industry: Retailing

2020: £193m 2019: £120m

University dropout Thirlwell launched Hotel Chocolat with his former colleague Peter Harris in 2004. Thirwell's father Edwin founded the Mr Whippy ice-cream operation and Prontaprint. The Royston-based retailer floated on the stock market in 2016 and after a delicious run for the shares Hotel Chocolat is now worth around £550m. There are 116 UK stores, 14 international sites and a boutique hotel with a cacao estate in St Lucia.

Thirlwell still runs the business and owns 31.5 per cent of the shares. His stake is now worth £173m - up £72m in 12 months. There was a £20m windfall at the float. Taking account of tax, dividends and other wealth should take Thirlwell to £193m.

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19. Lewis Hamilton

DOB: 07/01/85 Industry: Motor racing

2020: £187m 2019: £160m

Hamilton's tally of F1 championship wins is now just one behind the record of seven achieved by Michael Schumacher. Stevenage-born Hamilton began his racing career with McLaren, before moving to Mercedes in 2013. His contract pays him a basic wage of £30m a year, with a further £10m available in bonuses.

He also earns well from sponsorship and endorsement deals with brands including Sony, Bose, Puma, Tommy Hilfiger, Police, L'Oreal and Monster Energy. These commercial tie-ups are estimated to be worth $10m a year. Hamilton owns a £20m Bombardier jet to ferry him to and from races, and a £10m apartment in the modern Fontvieille district of Monaco. There is also a home in the mountains of Colorado. Hamilton's contract expires at the end of 2020. Ferrari and Red Bull have signalled that they are both interested in the 35-year-old driver, raising the prospect of a bidding war that would push him further up these rankings next year. Hamilton recently pledged $500,000 for the fire service and animal charities addressing the Australian wildfires.  

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20. Tom McMullen & family

dob: 28/07/76 Industry: Brewing

DOB: £186m 2019: £173m

Four McMullens serve as directors of their family's Hertford-based brewer, with Tom McMullen serving as joint managing director. Their ancestor Peter McMullen began selling beer illegally in 1827, went legit a few years later, and opened his first pub in 1836. The business nearly folded just after the Second World War when the then owner died and the taxman levied an inheritance tax bill of 163 per cent. The McMullens had to sell the family home to keep the business afloat.

As well as brewing Hopping Mad, Stronghart and other beers, McMullen operates around 125 pubs across Hertfordshire, Essex and London. There were profits of £15.2m on £86.7m sales in 2017-18. Net assets grew to £161.3m - up almost £11m. We value the company on that assets number. Past dividends and other wealth take the wider family to £186m.

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21. Jason Gissing

DOB: 25/10/70 Industry: Retailing

2020: £170m 2019: £80m

Gissing, born to a Japanese mother and English father, was one of the trio who founded Hemel Hempstead-based Ocado. The Oxford graduate met his fellow co-founders Tim Steiner and Jonathan Faiman while they worked at Goldman Sachs. They launched the online grocery retailer in 2000 and floated the business on the stock market in 2010 with a value of £940m. The shares have had a great run and now value Ocado at £8.9bn.

Gissing left the company in 2014, but still owns 1.68 per cent of the shares, a stake worth almost £150m. We reckon that with share sales of around £3.6m at the float and a more recent £15m disposal. Gissing should be worth at least £170m after tax.

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22. Neil Utley & family

DOB: 16/01/62 Industry: Insurance

2020: £160m 2019: £174m

Utley owns the Hertfordshire mansion once dubbed by the tabloids 'Beckingham Palace'. The insurance mogul bought the seven-bed Rowneybury House from David and Victoria Beckham for £11.3m in late 2013. The Sawbridgeworth property boasts a woodland chapel, fake ancient ruins and 17 acres of land. Utley made his money in the insurance world. He netted £13m from the sale of one company, using some of the proceeds to take control of the ailing Hastings Direct. He turned around the business and made £135m from selling 50 per cent to Goldman Sachs in 2013.

Hastings' shares have had an indifferent year, with the value of Utley's stake falling to just under £56m - down £15.6m on last year. But his 4.54 per cent stake should still have yielded £3.9m of dividends over the past year. Utley has recently been building a three per cent stake in the doorstep lender Non-Standard Financial, a holding worth £2m. An enthusiastic musician, Utley has launched his own music production company NUA Entertainment. His first signing was ex-Busted frontman Charlie Simpson. The falling share price of Hastings leads us to clip Utley to £160m.

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23. John & Liam Griffin & family

DOB: 01/08/42 and 09/03/73 Industry: Transport

2020: £150m 2019: £150m

Last December Liam Griffin launched a £125m bid for Addison Lee, London's second biggest minicab firm. Griffin's father John founded the business in the mid 1970s. By the mid-1980s he was driving a Rolls Royce - something he said helped reassure his staff they were onto a good thing. 'They needed to know I could pay them at the end of the week,' he once said.

Griffin senior is now retired after Addison Lee's £300m sale to an American private equity company in 2013. The younger Griffin served as chief executive until 2015, and remains a director. The Griffins' extensive charity work includes a £10m gift to a medical research institute in North London. We keep the Griffins at £150m this year.

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24. Stelio Stefanou

DOB: 06/11/52 Industry: Business services

2020: £140m 2019: £140m

Cyprus-born Stefanou sold his business services company Accord in 2007 for a reported £180m. A former High Sheriff of Hertfordshire, his assets include a Mayfair property once owned by the then Duke of Clarence before he became King William IV in 1830. Stefanou is a high-profile supporter of an initiative by Westminster's local authority urging wealthy individuals to voluntarily pay extra council tax. His home in the borough is worth around £50m and he said last year that he supported the scheme 'because it gave those who can afford it the chance to do the right thing'.

He was awarded an OBE for services to business in 2004. Stefanou should still be worth £140m after tax and charitable work.

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25. William Hughes & family

DOB: 21/07/41 Industry: Care Homes

2020: £137m 2019: £127m

Hughes owns and runs B&M Care, a Hemel Hempstead-based care home operator and developer. Born in Ireland, he came to England at the age of 16 and developed his carpentry and construction skills. He bought his first care home, Clare Lodge in St Albans, in 1975. The group now has 26 homes across Hertfordshire, Buckinghamshire, Berkshire, Oxfordshire and Northamptonshire.

In 2017-18 profits rose again to £14.6m on turnover of £53.2m. With £79.6m net assets, B&M Care is now a £130m operation. Dividends and other assets take Hughes to £137m.

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26. David Kahn & family

DOB: 24/07/31 Industry: Flooring

2020: £131m 2019: £135m

Letchworth Garden City-based Altro Group is a world-leading manufacturer and supplier of interior surfaces. The company invented its Altro safety flooring in 1947, taking inspiration from the Bauhaus movement. This sheet vinyl floor covering promises a smooth, slip-resistant surface.

The business has also moved into wall cladding. The Kahn family, led by chairman David Kahn, owns the business. Profits fell slightly to £10m on higher sales of £145.2m in 2018. With £92.8m net assets, Altro should be worth £115m. Past dividends - including a £2.2m payment in 2018 - add another £16m.

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27. Tony Kleanthous

DOB: 26/01/66 Industry: Football & property

2020: £131m (New entry)

Kleanthous owns and chairs Barnet FC. Born into a north London Cypriot family, he began his entrepreneurial career selling cars before moving into petrochemicals and mobile phones. More recently he has invested in medical imaging through his TIC Health, which owns highly mobile scanners providing cardiac screening for premiership footballers, and are also used by professional performers in the worlds of theatre, dance and entertainment.

Over the years Kleanthous has spent more than £60m on building a stadium and facilities for Barnet known as The Hive. He has also been a driving force behind the growth of women's football, in 2013 forming the London Bees who play in the FA Women's Championship. We see holdings of £131m in three Kleanthous companies and value him at that level.

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28. Michael Yarrow & family

DOB: 02/12/47 Industry: Pharmaceuticals

2020: £131m 2019: £139m

Yarrow runs Diomed Developments, a manufacturer of dermatological products. Founded in 1963, the Hitchin-based company trades as Dermal Laboratories. Its products are well-known among dermatologists, GPs and nurses and are widely prescribed for the treatment of a variety of skin disorders, such as psoriasis, eczema, dry skin conditions and acne, as well as other conditions which can be treated by applied medication.

Profits at Diomed, which is owned by the Yarrow family, fell to £7.7m on lower sales of £58.7m sales in 2017-18. We trim the value of the company to £120m, adding £11m to the Yarrow family for dividends and horse-racing assets.

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29. Brian Morrisroe

DOB: 31/08/55 Industry: Construction

2020: £130m 2019: £125m

Morrisroe worked on the foundations of the recently completed Tottenham Hotspur Stadium, helping finish the 61,000-seater north London football venue in time for the start of the current season. Brian Morrisroe set up his eponymous Borehamwood-based firm in the mid-1980s. Over the years it has come to specialise in groundworks and building reinforced concrete frames.

Despite 22 per cent lower turnover in 2017-18, profits dipped only slightly to £15.7m and the net assets number climbed to £55.4m. So we still value the operation at £120m. A separate construction firm, Morrisroe UK, is worth its £7m assets. We add a further £3m for a steady run of dividends.

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30. Hitesh & Dilesh Mehta

DOB: 02/09/56 & 29/02/60 Industry: Perfume

2020: £127m 2019: £126m

Hitesh and Dilesh Mehta set up Shaneel Enterprises in 1986. Today their perfume distribution business supplies fragrances to Tesco, Morrisons and a range of other big retailers. The family's Watford-based business also operates PerfumeShopping.com, an online retailer selling products from Calvin Klein, Hugo Boss and Tommy Hilfiger as well as celebrity ranges from Ariana Grande and Naomi Campbell.

Shaneel's profits fell to £9.6m on turnover of £131.1m sales in 2018-19. Net assets also climbed to £63.5m. We still value the operation at £120m. The fall in profits was largely due to £2.6m of directors' pay - to the three members of Mehta family who sit on the board. We add £7m for past dividends, property and other wealth.

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31. Michael & Mona Masterson & family

DOB: 20/12/50 & 01/01/52 Industry: Construction

2020: £126m 2019: £120m

Masterson came to the UK from the Irish island of Achill and has gradually put together a multi-skilled construction group. His Borehamwood-based empire includes Getjar, which makes concrete frames, and Glencoe Plant Services, which hires out plant and machinery to building firms. Another part, Atlantic Contracts, specialises in carpentry and joinery for hotels, hospitals and other clients. Masterson set up the business in 1980 and still chairs Getjar.

He and his wife Mona own all the shares. Profits rose again at their holding company to £11.1m on sales of £129.2m in 2017-18. We value the business at £115m. Dividends, a racehorse operation and other wealth take the Mastersons to £126m.

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32. Daniel Durkan & family

DOB: 09/09/64 Industry: Construction

2020: £125m 2019: £116m

Borehamwood-based Durkan has become a leading construction and development company across London and the Home Counties. Daniel's Irish-born father William set up the business in 1970. Daniel is executive chairman of Durkan now, having picked up the reins from his father in 2010. The developer and contractor focuses on new build, local authority refurbishment schemes and retirement developments across London and south-east England. In 2018 profits fell again to £7.9m - but this fall was largely due to a £6m dividend.

With turnover of £164.9m sales and £60.3m of net assets, the business should easily be worth £115m. Durkan Holdings is owned by overseas trusts, but we assume that the Durkan family are the ultimate owners. We add £10m for dividends and other wealth.

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33. Stephen Brooks

DOB: 30/03/62 Industry: Exhibitions

2020: £120m 2019: £120m

Brooks oversaw the sale of Mack Brooks in early 2019. The St Albans-based event organiser puts together exhibitions for a wide range of industries, including the rail, aviation, steel and chemicals sectors. Mack Brooks' roster now includes events in the UK, Europe, China, the USA, Singapore, India and Mexico. Last year's deal valued the business at £120m.

The firm was founded by Kenneth Brooks and Brian Mack in 1965. Stephen Brooks took over the operation in 2013 after previously working in marketing for Jaguar Land Rover. Brooks and his family were thought to own at least 75 per cent of the shares before the deal. After tax the Brooks family should still be worth £120m.

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34. Rick Willmott & family

DOB: 16/05/63 Industry: Construction

2020: £109m 2019: £100m

Letchworth-based Willmott Dixon had a strong year in 2018, with profits nearly tripling to £37m on turnover of almost £1.5bn. The construction company was founded in 1852, and Rick Willmott is the fifth generation of his family to run the business. Over the years Willmott has grown Be Living and Fortem, subsidiaries specialising in residential developments and building maintenance.

We value the Willmott Dixon group of companies at £250m. At least 35 per cent of the business is owned by members of the Willmott family - a stake worth £87.5m. A good run of dividends and other assets should add at least another £21m.

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35. Robert Weston & family

DOB: 11/07/55 Industry: Construction

2020: £106m 2019: £82m

Weston Homes recently began the £60m redevelopment of a Grade II-listed former military hospital in Aldershot. The project will deliver 140 new homes on the 12-acre site. Weston founded his Bishop's Stortford-based housebuilder in 1987, and he remains chairman and chief executive. In 2018-19 there were profits of £25m on £255.9m sales.

With £102.3m of net assets, we value the operation at £250m. Weston owns just over 41 per cent of the shares, a stake worth £102.5m. We add £3m for dividends and other wealth.

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36. Richard Rowlandson & family

DOB: 02/12/39 Industry: Property

2020: £90m (New entry)

Stanley Rowlandson began building his family's diverse business empire in 1932. He amassed 100 butchers and 60 newsagents, as well as undertakers, insurance brokers, petrol forecourts and a significant property portfolio. Stanley's son Richard now chairs the Potters Bar-based group, which today focuses on commercial and residential property.

The group - known these days as The RO - includes the residential developer Metis Homes and the holiday lodge firm Charteroak. There were profits of £5.6m on turnover of nearly £35m in 2018-19. There are net assets of nearly £90m on the balance sheet, and we value the family at that level. Richard Rowlandson, who like his father trained as an accountant, runs the family-owned firm.

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37. Phil Wallace & family

DOB: 22/10/49 Industry: Food

2020: £90m 2019: £110m

Wallace has said he has no plans to sell League Two Stevenage FC, despite approaches from potential buyers in China, the USA and Canada. 'I have no intention of leaving just yet,' he said. 'I would much rather enjoy some years of Stevenage being a bigger spending club, attracting new supporters and aiming for the Championship.' Wallace (right) saved the club from bankruptcy in 1999, and since then he has spent a small fortune improving the ground and creating a new training facility.

After starting his career at a London stockbroker, Wallace has built his fortune through food group Lamex. He began as an employee of the Broxbourne-based food procurement and logistics specialists. Within three years he was a director, and during the 1980s he had become the majority shareholder. Profits fell sharply to £13.4m on £1.2bn turnover in 2018-19. Wallace and his family own about 24 per cent of the firm. With other wealth, the Wallaces should be worth around £90m.

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38. Farouq & Haroon Sheikh

DOB: 13/10/58 and 04/03/56 Industry: Care homes

2020: £86m 2019: £65m

Potters Bar-based CareTech provides accommodation and support for children requiring foster care and people of all ages with special needs. A strong year on the stockmarket for the care provider's shares has boosted the wealth of the Kenyan-born Sheikh brothers, who founded the business in 1993.

Farouq is CareTech's executive chairman, with Haroon serving as chief executive. The pair bought out private equity investors in 2004, and floated the company on the stockmarket in 2005. CareTech is now worth over £510.4m. The Sheikhs sold around £12m worth of shares at the time of the float, and another £6.7m in 2017. Their 11.56 per cent stake is now worth £59m - up £21m in a year. After tax and with other property assets, the Sheikh family should be worth £86m.

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39. Guy Ritchie

DOB: 10/09/68 Industry: Films

2020: £77m 2019: £67m

The Hatfield-born filmmaker does not have a problem attracting killer casts for his gangster flicks - sometimes in the most unlikely roles. The Gentlemen, released in January, features Hugh Grant as a sleazy private investigator and Michelle Dockery - better known as Downton Abbey's irreproachable Lady Mary - playing the part of a drugs lord's foul-mouthed, cockney wife. Ritchie also roped in Hollywood A-listers Matthew McConaughey and Colin Farrell for his latest caper. Ritchie's film career took off in his early 30s, with the early hits such as Lock Stock and Two Smoking Barrels and Snatch.

Since then the writer-director - who was married to Madonna for eight years - has had a string of other box office successes including two Sherlock Holmes films, The Man from Uncle and King Arthur: Legend of the Sword. But his 2019 live action version of Aladdin for Disney (Ritchie is pictured during filming with Will Smith) is thought to have been his most commercially successful film so far, taking more than $1bn at he box office worldwide. His divorce settlement from Madonna included the couple's country estate Ashcombe House in Wiltshire along with a £4m townhouse, their pub and a £3m property in New York. The real size of the settlement was put at between £39m and £46m. We see £3.8m on the balance sheet of Ritchie's various film companies in 2017-18, up £2.8m in a year. But this only provides part of the picture. Aladdin's runaway success and another new project called Cash Truck justifies raising Ritchie by £10m to £77m this year.

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40. Anthony Joshua

DOB: 15/10/89 Industry: Boxing

2020: £75m 2019: £55m

Watford-born Joshua regained his WBA, IBF and WBO belts with victory over Andy Ruiz Jr in their December 2019 rematch. The 30-year-old champion will not be short of further opportunities to bolster his bank balance. He has already been ordered to make title defences against Kubrat Pulev and Oleksandr Usyk. Joshua is said to have earned £18m for beating Joseph Parker in 2018, £20m from his fight with Alexander Povetkin, and another £46m from the Ruiz rematch (Joshua is pictured celebrating that victory in Saudi Arabia). This takes his gross career earnings from fights to easily more than £100m. However, that figure takes no account of tax or the cost of employing his trainer, coach and the rest of his support team.

But Joshua has also assembled a lucrative array of commercial backers away from the ring, including Hugo Boss, Jaguar, Lucozade and British Airways. Annual income from these interests has been estimated at £10m a year. There are also signs that he is being careful with his money. His manager Freddie Cunningham has said that the private jets, flash cars and expensive watches that gild Joshua's life are largely sponsored. 'We've never paid for a private jet or a helicopter in our lives, and he gets a signature car from Land Rover,' Cunningham said. 'He's not spending that money. He's accumulating money. He's living a lifestyle that probably everyone wants him to live, or see him live, but he's doing it in a smart way.' We put Joshua at £75m this year.

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41. Stephen Dixon & family

DOB: 20/04/63 Industry: Construction

2020: £70m 2019: £70m

Dixon's father Sir Ian Dixon helped build up Willmott Dixon, the Hitchin-based construction group. Founded in 1852, the company now specialises in hospitals, leisure centres, schools and other public and private sector buildings. In 2018 Willmott Dixon's parent company Hardwicke Investments showed profits of £37m on record sales of nearly £1.5bn. It has £73.9m net assets.

We value the company at £250m and the Dixon family's stake at around £47m. The company has paid out dividends of more than £32m over the past five years. With past salaries, dividends and other assets, the Dixon family should still be worth £70m.

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42. John Lawson & family

DOB: 11/05/32 Industry: Builders' merchants

2020: £70m 2019: £65m

After completing a spell of National Service in the early 1950s, Lawson joined his family's fencing contracting business. The company had been started in 1921 by his grandfather. He was just 20 years old when he took over the business after the deaths of both of his parents. Over the years the Colney Heath-based firm began making shed and fencing materials; Lawsons became the first company to sell fencing panels cut to length and ready treated.

Today the business is now a fully-fledged timber and builders' merchants, with 17 branches. In 2018 profits rose to £7.4m on record turnover of £95.1m. With £50.3m of net assets on the balance sheet, this is now a £70m business. The Lawson family owns most of the shares and should be worth that sum.

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43. Bryan Duffy & family

DOB: 21/03/43 Industry: Leisure

2020: £66m 2019: £65m

Duffy owns and chairs Instant Access Technologies, a tech firm that develops loyalty schemes for retailers and other businesses. Bupa, Nestle and Coca-Cola are all clients of the Ware-based operation.

Duffy previously sold his online reservation service Hostelbookers.com in 2013 for £60m. His main holding company, MBI MBO, showed £16.1m assets in 2018 - up £600,000 in a year. Duffy and his family own it all. We raise the Duffys to £66m.

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44. Alan Moore

DOB: 29/05/50 Industry: Electrical Goods

2020: £63m 2019: £63m

Dubliner Alan Moore runs and owns Medlock Electrical Distributors, the UK's largest independent electrical wholesaler. The Waltham Cross-based business dates back to 1910, and now has 48 branches selling lighting, lamps, cables, security systems and other accessories. Profits fell to £4.8m on lower turnover of £67.3m sales in 2018-19. A £7.5m dividend was paid to Moore in 2016-17 - following on from a £2.5m payout the previous year.

With assets of £26.6m, we now value the operation at £48m. Moore also owns the separate business Abbey Cross, which makes safety equipment and is worth its £7.6m net assets. We add a further £7m for dividends and other wealth. This takes Moore to £63m.

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45. Rory Bowman & family

DOB: 09/10/60 Industry: Food

2020: £60m (New entry)

Bowman Ingredients provides the taste and texture for countless pub and supermarket meals. The original Bowman company was a family-run milling operation set up in 1857. But since the early 1990s the Bowmans have concentrated on providing batters, breadcrumbs and other coatings for supermarkets, pub chains and other clients. Rory Bowman is the chief executive of the Hitchin-based firm and is the great-great grandson of the founder. There are now Bowman operations in South Africa, Thailand and Australia.

Profits rose by about 75 per cent to £6.8m on £49m sales in 2017-18. With £30.4m of assets on the balance sheet, the family-owned business should be worth £60m.

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46. Liam Lynch

DOB: 13/07/54 Industry: Construction

2020: £54m (New entry)

Lynch, 65, runs and owns L Lynch, a plant-hire business he set up more than 35 years ago. Profits rose strongly to £5.4m on £63.9m sales in 2018-19.

The Hemel Hempstead-based operation has nearly £15m assets and we value it at £30m. Another £18.6m of net assets can be seen in the separate L Lynch Holdings, and we add a further £5m for dividends and other pay. This takes Lynch to £54m this year.

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47. David Underwood & family

DOB: 22/08/52 Industry: Pharmaceuticals

2020: £52m 2019: £49m

Quanticate has opened new offices in India and Canada over the past two years. The Hitchin-based firm provides clinical research, statistical support and a range of other services for pharmaceutical companies. Statistician David Underwood was working for GlaxoSmithKline when he saw the opportunity to create a business providing expert statistical services for the pharma and healthcare industry. Quanticate is now thought to be the largest data-focused clinical research organisation in the world. Profits rose to £5.2m on £18.8m sales in 2018.

Underwood and his family have a 70 per cent stake in the £70m operation - a holding worth £49m. We add £3m for dividends and other wealth.

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48. Derek Beevor

DOB: 24/06/55 Industry: Software

2020: £51m 2019: £160m

After serving as a paratrooper Beevor set up a road-haulage company, but grew frustrated with the lack of software to help him manage his fleet of 20 vehicles. So in 1984 he launched Road Tech Computer Systems, which helps transport firms plan routes and monitor their trucks in real time.

In 2018 Beevor decided to give away 51 per cent of the shares in the £100m business to the staff through an Employee Owned Trust. He retains a 49 per cent holding in the Radlett-based business, which made a profit of £5.3m on turnover of £11.7m in 2018-19. Taking account of past dividends and other wealth Beevor should easily still be worth £51m.

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49. Jeremy Clayton & family

DOB: 22/08/56 Industry: Food & property

2020: £50m 2019: £50m

Clayton and his family own the Bury Lane Farm Shop near Royston. The operation began as a small fruit and veg stall almost 30 years ago and now has strawberry tunnels, glasshouses and a farm-themed fun barn for children.

Turnover at the main family holding company E.W. Pepper rose to £7.7m in 2018. The latest accounts showed the family own residential and commercial property worth £33.5m. We still put the Claytons at £50m.

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50. Tony Reynolds & family

DOB: 14/01/64 Industry: Food

2020: £50m (New entry)

Reynolds' grandfather William started the family's food empire with a fruit and veg stall at Hackney's Ridley Road market in 1945. Today Letchworth-based Reynolds food supplies more than 3,000 different types of fresh produce to pubs, restaurants, hotels and schools.

Profits rose to £5.6m on turnover of £216m in 2018. We value Reynolds - and the family who own it - at £50m.

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