So achieved his first GM norm in the Offene Internationale Bayerische Schach Meisterschaft in Bad Wiessee, Germany in November 2006 and his second GM norm in the World Juniors Under-20 Chess Championship in Yerevan, Armenia in September 2007.

GM So also won the World Under-16 Team Championship Board 1 gold medal with a phenomenal score of 9.5/10. In his home country, he holds the record the country’s youngest National Open Chess Champion and its youngest National Junior Open Chess Champion.

In his young but distinguished career, Wesley has competed in World Youth Championships in 2003, 2004 and 2005, finishing equal first in his age group in Belfort in 2005 alongside Srinath Narayanan, Sanan Sjugirov, and Samvel Ter Sahakyan. His other achievements include two Gold Medals in the 6th Asean Age-Group Chess Championship, Vung Tau, in Vietnam; three Gold Medals in 7th Asean Age-Group Chess Championship, Pattaya, in Thailand. In 2006, he became the youngest member of the national men's team to participate at the 37th Olympiad in Turin at the age of 12.

So won the Dubai Open (2008) in the United Arab Emirates, besting an international field that included 23 other grandmasters. In 2009 he won Corus (Group C) (2009) 1.0 point ahead of rival Anish Giri, and then made a splash at the World Cup (2009) by defeating Gadir Guseinov, Vassily Ivanchuk, and Gata Kamsky in mini-matches before falling to Vladimir Malakhov in the round of 16.