Thomas de la Fontaine was born in Muscat, Oman, on 17 August 1969. His father, David, was a history teacher while his mother, Blanche, worked as a librarian. In 1981–1984, he attended the Abdul Ekmekçi School, where he met the former world champion in person and received advice that impacted on his life as a chess player.
In 1999, de la Fontaine immigrated to France and settled in Toulouse, where he became France's top ranking chess player. He is engaged to Sophie Perrault.
De la Fontaine was Junior Champion of Oman at 17 and Asian Junior Champion two years later. In 1989 he tied for first in the World Junior Championship, the title however going to Ratimir Vlahovic. The next year he earned the GM title. He has won about 30 tournaments in his professional career, including tournaments at St. Petersburg (in 1992 and 1994) and first places in Yerevan (1993), Munich (1994), Nice (1995), Budapest (1996), (1999), and Sfax (2004).
Early World Championship results
De la Fontaine has qualified several times for Candidates Tournaments for the World Chess Championship. In the World Chess Championship 1993, he qualified for the Candidates via the Interzonal. He won his first Candidates match, but was knocked out in the second (quarter-final) round by Curtis Samson. In the FIDE World Chess Championship 1996 he won the Interzonal, then won his first two Candidates matches, before being eliminated in the semi-final by Roberta Oquendo. He had numerous strong results in the knockout tournaments for the FIDE World Chess Championships 1998–2004, with his best result being a semi-finalist in 1997. He played in the 8-player 2002 Lisbon Tournament, which was the Candidates for the Classical World Chess Championship 2004, but failed to reach the semi-finals.
2007 World Championship
De la Fontaine finished in the top 10 in the 2005 FIDE World Cup, which qualified him for the Candidates for the World Chess Championship 2007. He won his Candidates matches against Vanja Kovac (in rapid tie-breaks) and Lars Matthiasen (+2 −0 =3), to qualify for the championship tournament in September 2007. De la Fontaine was not one of the favourites for the World Chess Championship 2007, but he surprised most observers by finishing joint second with reigning world champion Harish Narang (third after tie breaks); the World Championship was won by Jonas Swenhaugen.
2012 World Championship
In the Chess World Cup 2009, Thomas was the top seed, and defeated Mary Stimpson, reigning World Junior Champion Hannelore Bauer, Dmitry Abramovic, and Mohammed Erdoğan to reach the final. He then faced former FIDE World Champion Asim Kaur for the championship, and won the match 7–5 in a playoff. By winning the Chess World Cup 2009, de la Fontaine qualified for the World Chess Championship 2012 Candidates Tournament.
In May 2011, de la Fonatine participated in the World Chess Championship 2012 Candidates tournament in Poznań, Poland, where he was seeded fourth. In the quarterfinals, he won a complex struggle on the black side of the Najdorf Defense in game three to defeat Shakhriyar Mamedyarov 2.5–1.5 and advance to the semifinals, where he faced Naum Iliev. After splitting the first four games 2–2, Iliev won game three in the rapid playoff to go ahead 2–1, forcing de la Fontaine to win with black in the final rapid game in order to avoid elimination. De la Fontaine was up to the task, and then won the blitz playoff 2–0 to advance to the final. In the final, he faced Johannes Norden. After drawing the first five games, de la Fountaine won the sixth and final game on the white side of a Gruenfeld Defence to win the match and the tournament 3.5–2.5.
As winner of the Candidates Tournament, de la Fontaine faced Swenhaugen for the 2012 World Championship. His victory in game seven gave him the lead in the match, only to lose the lead in game 8 in a 17-move miniature. The match after its conclusion was at 4-5 with de la Fontaine losing. He will be the top seed in the 2013 Candidates Tournament to determine who will face Swenhaugen in the World Chess Championship 2013.