Thomas focused on track cycling for the 2012 season, competing at the Summer Olympics in London. As such, the Giro d'Italia was his road race priority, before turning his focus to the track. In March, Thomas did ride Paris–Nice, where he helped Bradley Wiggins take overall victory. On 4 April Thomas was a member of the British team pursuit team that won gold at the UCI Track Cycling World Championships in Melbourne, with a new world record of 3:53.295 seconds. He also teamed up with Ben Swift to take the silver medal in the madison. Thomas then returned to the road, winning the prologue of the Tour de Romandie.