Niel is the founder of Iliad, a telecommunication services provider. The Paris-based company controls the Free brand in France where it has 7.6 million fixed broadband customers and about 15.5 million mobile subscribers. Iliad also operates in Italy and Poland and had revenue of 10.3 billion euros ($11.7 billion) in 2025.
The majority of Niel's fortune is derived from Iliad, a French telecommunications company. The company has about 7.6 million fixed subscribers and 15.5 million mobile subscribers in France, according to its website.
He held 96% of the business as of Sept. 29, 2021, according to the company. The billionaire increased his stake during 2021 after holding a 70% stake in December 2020, according to Iliad's annual registration document. Iliad is valued in this analysis based on reported financial results and the average enterprise value-to-Sales and enterprise value-to-Ebitda multiples of three publicly traded peers: Vodafone Group PLC, Telefonica SA and Tele2 AB.
A liability is included based on an analysis of insider transactions, dividends, market performance, taxes and charitable contributions. It includes a calculation of the post-debt value of other asset purchases.
He controls 25.5% of Unibail-Rodamco-Westfield, according to the 2024 registration document. The billionaire owns a majority stake in the French daily newspaper Le Monde, according to a January 2022 report.
He also controls investment fund Kima Ventures, which has invested in 50 to 100 companies a year, and owns the music publishing catalog of French singer Claude Francois, the writer who wrote the original French version of the song "My Way," made famous by Frank Sinatra. These assets aren't included in his net worth calculation. People familiar with the catalog, who asked not to be named because the matter is private, said the value is nominal relative to Niel's total fortune.
Xavier Niel was born in Creteil, France, on Aug. 25, 1967, to a father who studied law and medicine and a mother who supported the family as an accountant. He began his career at age 16, when he dropped out of high school and created chat services for Minitel, a French precursor to the World Wide Web.
That business led Niel to create a number of companies, including some for sex chat service Minitel Rose. He sold most of them in 1997, with the exception of two peep shows, one in Paris and one in Strasbourg. Holding on to them proved troublesome seven years later, when French police raided his apartment and jailed him pending charges for pimping and tax evasion. He was fined 250,000 euros for non-declared earnings and cleared of the procurement charges, avoiding a two-year prison sentence.
Niel bought Fermic Multimedia in 1991, a company specialized in software for Minitel that was on the verge of bankruptcy. He used it to create 3617 Annu, the first online reverse directory that allowed Minitel users to find the names attached to telephone numbers. He invested in Worldnet two years later, the first French internet service provider and sold his stake seven years later for 40 million euros.
The billionaire introduced Free in 1999, an Internet service provider that had quick success by providing customers with an access modem for free, and charging for a discounted dial-up internet service. Free is now France's second-largest Internet service provider. He expanded Free's business by creating Freebox, the first set-top box to provide telephone, Internet and television through one service in 2002. Iliad, the parent company of Free, listed on the Paris stock exchange in January 2004.
Niel introduced the company's first mobile telephone service in 2012. The service offered unlimited calls and data for 20 euros a month and a two euro plan that included two hours of calls and data a month.
He joined an investment partnership that acquired two-thirds of French daily newspaper Le Monde in 2010. He formed Kima Ventures, an angel investment fund which invests in 50 to 100 start-ups per year. He also owns the music publishing catalog of French singer Claude Francois, who wrote the single "Comme d'habitude," its melody made famous by Frank Sinatra with his translated version, "My Way."
Xavier Niel launched 42, a free information technology university aimed at training 1,000 developers a year, in March 2013. He announced the launch in 2016 of the world's largest digital incubator, six months later. Niel lives in Paris.