The family behind Europe's biggest steelmaker has lost more than £2 billion in the past year, the Sunday Times Rich List reveals.
Steel magnate Lakshmi Mittal and his family, who own ArcelorMittal, were number one eight years ago with a wealth of £27.7 billion - the biggest fortune ever achieved by anyone on the list.
The Mittals have now dropped to 11th on the list and have a much smaller fortune of £7.12 billion after losing £2.08 billion in the past year.
Formula One champion Lewis Hamilton, who is Britain's wealthiest sportsman, is new to the list and is worth £106 million, according to the guide to Britain and Ireland's richest people.
Entrants had to have at least £103 million to make it onto the 2016 list, up from £100 million last year.
Earlier this month it was reported that ArcelorMittal board member Wilbur Ross could be among investors expected to be contacted about buying some of Tata's business interests in the UK.
At the top of the 2016 money pile are property tycoons the Reuben brothers, whose ownership of London's Millbank Tower and the John Lewis headquarters in the capital have helped them build up £13.1 billion.
Mumbai-born David and Simon Reuben, who also own London Oxford Airport and London Heliport, have increased their fortune by £3.4 billion in the past year.
Brothers Sri and Gopi Hinduja, who run the Hinduja Group, remain in second place a year on with an unchanged fortune of £13 billion.
Completing the top three is Warner Music owner Len Blavatnik, who despite a drop two places after a reduction in wealth by £1.58 billion, has £11.59 billion.
Adele was named as Britain's richest ever female musician, with an £85 million fortune.
Footballer Wayne Rooney, who is worth £82 million, was named the richest sportsman aged 30 or under.
British comedian and the creator of Ali G, Sacha Baron Cohen, has made it onto the list for the first time.
The 44-year-old has a fortune of £104 million along with his actress wife Isla Fisher, 40.