He was first elected to Dail Eireann in the 2011 General Election and was the youngest member of the 31st Dail. During that Dail term, Simon served as a member of the Public Accounts Committee, Oireachtas Committee on Finance, Public Expenditure and Reform, Secretary of the Fine Gael Parliamentary Party and Co-Convenor of the Oireachtas Cross Party Group on Mental Health, before being appointed in July 2014 as Minister of State in the Departments of Finance, Public Expenditure and Reform and the Department of the Taoiseach with Special Responsibility for OPW, Public Procurement and International Banking (including IFSC).