After five seasons of karting, he stepped up to single seater racing in 1998 in the UK Formula First championship, in which he dominated with 12 wins.

In 2004 he became the first driver for eleven years to win a round of the British Formula 3 Championship whilst not driving a car from the Dallara company.

In 2008, he signed to the SAS Lechner Racing team with teammate Damien Faulkner for the F1-supporting Porsche Supercup series.

In 2010, he retained his seat for Strakka Racing in the Le Mans Series however the team moved down to the LMP2 category now using a HPD ARX-01c.

The 2011 Le Mans season was good for Watts, once again being the strongest link in the team constantly qualifying the Strakka car high up the LMP2 field.

In 2012, Strakka retained Watts, who went on to put in a hero's drive at the World Endurance Championship round at Silverstone England, by doing a double stint of three-and-a-half hours to finish within 0.6 secs of 4th place.