[3] On 21 September 2011, he made his debut for Southampton, playing the full 90 minutes in the League Cup third round match against Preston North End.

[7] He joined Dagenham & Redbridge on a month's loan on 23 February 2012,[8] making his debut for the club two days later, in a 0–0 draw against Plymouth Argyle.

[14] Reeves played his first match in his second loan spell, providing an assist for Freddy Eastwood, in a 1–1 draw against Torquay United.

[15] Reeves played in the final of the Football League Trophy against Crewe, where he came on as a substitute for Bilel Mohsni in the 57th minute, as Southend lost 2–0.

[19] After appearing on the bench throughout August and September, Reeves played in an unusual position as a striker when he scored his league goal of the season, in a 3–2 win over Rotherham United on 19 October 2013.

[34] Reeves finished his first season at Milton Keynes Dons, making thirty-five appearances and scoring eleven times in all competitions.

Reeves played his first Championship game in the opening match of the 2015–16 season, where he set up a goal for Dean Bowditch, in a 4–1 win over Rotherham United.

[49] However, on 21 August, Reeves suffered a hamstring injury, which he sustained during a match against Preston North End which ruled him out for a month.

[52] On 3 August 2017, Reeves signed for League One side Charlton Athletic on a two-year contract., rejoining his former manager, Karl Robinson.

[55] On 1 August 2019, Reeves returned to Milton Keynes Dons on a free transfer for a second spell having spent much of pre-season training with the club.

[64] Reeves received his first international call-up for Northern Ireland in February 2014, qualifying as his grandparents hail from Fermanagh.