Coleman elected to the House of Representatives at the 2013 federal election, holding the New South Wales seat of Banks. In December 2020 he was appointed Assistant Minister to the Prime Minister for Mental Health and Suicide Prevention. He previously served as Minister for Immigration, Citizenship, Migrant Services and Multicultural Affairs in the Morrison Government from August 2018, although in December 2019 he took indefinite leave for personal reasons. He had earlier served as Assistant Minister for Finance in the Turnbull Government from 2017 to 2018.