As a player he played as a scrum-half for St Helens, Salford Red Devils, Wigan Warriors, and Catalans Dragons in the Super League and Widnes Vikings in the RFL Championship, in addition to various loans.

After coming through the junior ranks at St Helens, Smith made his Super League début for the club in 2006 in a match against Huddersfield Giants.

[citation needed] Two days after making his England début against The Exiles, Smith completed his switch to Wigan on 6 July 2012, after a successful negotiation between the clubs to the early release from his Salford contract.

[4] In 2013, Matty received the number 7 jersey formerly worn by the likes of Thomas Leuluai, Adrian Lam, Shaun Edwards and Andy Gregory.

On Friday 19 September, a night after Smith scored 21 points in the 57–4 playoff rout against the Huddersfield Giants, he signed a new four-year contract with the Warriors.

On 23 June 2017, Smith kicked a long range field goal in the final second of the match against Salford to secure Saints a 25-24 victory.

In 2015, Smith set up a business with former Salford team mate Stefan Ratchford called Future Stars, which runs coaching sessions for junior rugby league players.