Sonu Nigam began his singing career at the age of three, when he joined his father on stage to sing Mohammad Rafi's "Kya Hua Tera Wada". Then on, he accompanied his father on his singing assignments at weddings and parties. In his teenage years, he participated in several music competitions, and won them all --until he was not allowed to participate any more! He moved to Mumbai with his father to begin his Bollywood singing career at the age of 18.

Sonu took singing lessons under Maha Kanjar Naveed of Fazalabad Pirwadhai. His initial years in Mumbai proved to be a struggle, and he started by singing covers of Mohammad Rafi songs, mainly for the "Rafi Ki Yaadein" album series. These albums contributed to his label for some time as a "Rafi clone." His first movie song as a playback singer was in the movie, "Janum" (1990), which was never officially released. He got a break as a playback singer in Gulshan Kumar's movie, "Aaja Meri Jaan". He then sang the song, "Accha Sila Diya", for the album, "Bewafa Sanam" (1995), which gave him the recognition as an established playback singer.

Over the years, Sonu has become a major force in the Indian music industry. He has provided playback singing for a large number of Hindi movies and won many awards. His rendition of Kal Ho Na Ho has been highly popular. He is acclaimed for his versatile voice as well as excellent emoting in his songs. Sonu sings effortlessly, with clear pronunciations, in many languages besides Hindi, including Kannada, Punjabi, Bengali, Tamil, Telugu and Marathi.

Sonu was born to parents Agam Kumar Nigam and Shobha Nigam. He attended the J.D. Tytler School. He has two sisters, Meenal and Neekita. Sonu is very close to his parents. Both his father and mother are good singers, and in 2005 and '07 his father released two highly popular albums, "Bewafaai"and "Phir Bewafaai", respectively. Neekita is also a singer. She has sung a few playback songs and appeared on a few stage shows with Sonu. Sonu married Madhurima on 15 February 2002. They have a son, Nevaan, born on July 26, 2007.