Born in Ireland, Smith came to prominence in 2010, finishing as runner-up to Ben Greenhalgh on the television show Football's Next Star.
[3] In November 2011, Smith joined Isthmian League side Wealdstone on loan until January 2012, along with Britt Assombalonga.
[6] His professional debut for Watford came on 18 August 2012, in a 3–2 victory over Crystal Palace in the Football League Championship, replacing Sean Murray as a substitute.
[9] He scored his first goal for Plymouth in an EFL Trophy tie against former club AFC Wimbledon on 4 October 2016.
[10] Having helped Plymouth Argyle to achieve promotion to League One, Smith was released at the end of the 2016–17 season.