Sinach hails from Ebonyi State, Eastern Nigeria, and is the second daughter of seven children.
Sinach started singing for family and friends in 1989 as a hobby, while working as a staff and choir member in Christ Embassy, Pastor Chris Oyakhilome’s Church. She studied physics and graduated from the University of Port Harcourt, Rivers State, Nigeria. She considered relocating from Nigeria after her University education, but was advised against it by Pastor Chris Oyakhilome.
In 2014, Sinach married Joseph Egbu in her home Church Christ Embassy. On 17 November 2019, at the LIMA Awards Pastor Chris Oyakhilome, announced the arrival of Sinach’s first child.
As a child, Sinach stated she had dreams, where she saw herself singing to large crowds, but didn’t actively pursue anything musically as a career besides joining the choir, and also working as an administrative staff in the Church. Sinach had written many songs before she released her first album, Chapter One in 2008. Her song ‘This Is Your Season’ won the Song of the Year award in 2008.
Speaking on how she came by her stage name Sinach, she said: “I chose that from my name Osinachi because it is easy to pronounce and catchy”.
In 2016, Sinach was the first recipient of the LIMA Songwriter of the Decade Award, recognizing her contribution to gospel music in the previous decade. Her songs were being sung in many countries,  translated to many languages, around the world. That same year, she received the African Achievers’ Award for Global Excellence. Also that same year, for the second time in a row, she won the Western Africa Artist of the Year by Groove Awards in Kenya, and was listed by YNaija alongside Chris Oyakhilome, Enoch Adeboye as one of the Top 100 Influential Christians in Nigeria.
As a songwriter, Sinach has written over 200 songs and won several awards. Her song ‘This Is Your Season’ won the Song of the Year award in 2008. One of her most popular songs is ‘I Know Who I Am’.