The versatile singer started performing at the tender age of four years, while accompanying his father, Agam Kumar Nigam, for a stage show.
He started his Bollywood career at the age of 19.
In 1995, Sonu became popular as a television presenter by hosting one of the major singing reality shows on Indian television, 'Sa Re Ga Ma'.
He tasted success in the film industry with the song "Sandese Aate Hai" from the film 'Border' (1997).
The year 1999 proved to be a turning point in his career, as his album 'Deewana' was released and became a huge hit topping the charts. In the same year, he sung 'Yeh Dil Deewana' from the movie 'Pardes', which strengthened his foothold in Bollywood and marked his unique style of singing.
The singer has won several honours including two Filmfare awards, three IIFAA awards and one National award for the title track of 'Kal Ho Naa Ho.'
Influenced by the legendary pop singer Michael Jackson, Sonu released a tribute song 'The Beat of Our Hearts' in memory of the late singer Michael Jackson.
His other international projects include collaboration with American pop singer Britney Spears. He had also recorded a song with British singer-songwriter, rapper Jay Sean.
Sonu has judged many popular reality shows on television, like Amul STAR Voice of India, Chhote Ustaad - Do Deshon Ki Ek Awaaz, X Factor (India), Indian Idol.
The singer has also acted in few films including 'Jaani Dushman: Ek Anokhi Kahani', 'Kash Aap Hamare Hote', 'Love in Nepal' and others.
Sonu recently garnered huge appreciations with the song "Abhi Mujhme Kahin" - from the film 'Agneepath'.
Sonu has been actively involved in various philanthropic causes for Dignity Foundation, various cancer organisations, leprosy organisations, blindness organisations, women's welfare organisations, Kargil war affected families, and earthquake affected families.
The singer married Madhurima on 2002 and has a son named Nevaan.
Recently the singer is making waves in Marathi music industry, with his latest song 'Matching Navra' from the film.
Legendary singer Lata Mangeshkar wished the singer on his special day on Twitter.
"Namaskar. Aaj hum sabke priya gayak @sonuniigaam ka janamdiwas hai,meri taraf se sonu ko bohot pyar,badhaai aur aashirwad. Tathastu (Today is Sonu Nigam's birthday and I express my love and blessings for him on this day)", she tweeted.
Actor-singer Ayushmann Khurrana also tweeted:"@sonuniigaam Happy Bday Sonu da!"