Born in India, he moved to Wolverhampton, West Midlands, at a young age, and now lives in Hounslow, Greater London.

[5] Singh took up refereeing in 1985,[1] after taking his exam in order to improve his frequent outings as club linesman for the youth team he managed.

[10] He has refereed at international level taking charge of a friendly game between China and UAE in October 2011.

[14] On 13 August 2022, Sunny became the first British South Asian to referee an EFL fixture, since his father, for over a decade.

[15] On 9 March 2024, Sunny became the first British South Asian to referee a Premier League match, blowing his whistle in the game between Crystal Palace and Luton Town.