Between 2011 and 2012, Sloan made 21 senior international appearances for Ireland. In June 2011 he made his senior debut for Ireland against China. He subsequently represented Ireland at the 2011 Men's EuroHockey Nations Championship and at a 2012 Men's Field Hockey Olympic Qualifier. In April 2012 Sloan made his last appearance for Ireland in a 2–1 away win against Germany. Sloan and David Ames both scored for Ireland. In January 2013 Sloan and Ames announced that they were switching allegiances from Ireland to England/Great Britain.