 Milsom signed for League One club Rotherham United on a six-month contract on 24 June 2013.After being on the bench for the first two games of the season, Milsom made his debut for the club, where he came on in place of Michael O'Connor in the 85th minute, in a 2–1 win against Crawley Town on 17 August 2013.He then scored his first goal for the club in a 3–1 win over Sheffield United on 7 September 2013, where he "controlled smartly before firing a low drive from the edge of the box which beat the outstretched hand of Howard before smacking the inside of the post enroute to the net."