Kelly joined Reading on 11 January 2013, signing a -year contract. He made his début on 19 January in Reading's 2–1 away win over Newcastle United at St James' Park, made his home début a week later against Sheffield United in a 4–0 FA Cup win, and soon afterwards, stated that "regardless of what happens now and for the rest of the season, coming here is the best decision I've made in football". Kelly started every game in what remained of the season, and the team were relegated to the Championship.