 Ultimately, the Liberals were able to form government in the 38th parliament of W.A.in alliance with the WA Nationals, supported by three independents.Led by Premier Colin Barnett, Day held the following ministerial portfolios;
He was also the Minister for Environment and Minister for Youth from 22 November to 14 December 2010, having temporarily taken over Donna Faragher's portfolios, and served as Leader of the House for 4 years from 21 March 2013 to 11 March 2017.