Mugabo is the founder and chief executive of the Sonia Mugabo fashion label, which is named after her. She established her fashion label in 2013, after graduation from university. The label made its first public showcase in October 2013 at the "Kigali Fashion Week". As of November 2017, the label develops two collections annually. Sonia Mugabo designs clothes for both men and women, using locally sourced material.
