Tardif began his career as a trainee with Portsmouth, turning professional in the 1998 close season. He joined Havant & Waterlooville on loan in August 1999, playing in the first eight league games of Havants' first season in the Southern League Premier Division. He also had a spell on loan with Newport (Isle of Wight) from March to May 2000 and finally made his Portsmouth debut in their 2-1 defeat at home to Tranmere in the FA Cup on 6 January 2001. He made four further appearances for Portsmouth that season, all in the Championship as Portsmouth successfully avoided relegation. His only other appearance for Portsmouth came on 27 August 2001 when Tardif played in their 4-1 win at home to Grimsby Town.
He spent the 2002-03 season on loan with Bournemouth, playing 14 games in all competitions and, after a spell on loan with Newport (Isle of Wight), in October 2003 joined Havant & Waterlooville on a month's loan, as cover for the injured Gareth Howells.
Released by Portsmouth, he joined Oxford United in May 2004, on a two-year contract. He was a regular the following season. However, he found first-team football hard to come by in later seasons, particularly under Jim Smith when Billy Turley kept him out of the side to the extent that he had a transfer request accepted by Oxford in December 2006. In September 2007, he retired from professional football in order to start a new career, although planned to continue playing semi-professionally.
Tardif played one game as a triallist for Eastleigh in October 2007, and joined Basingstoke Town in December 2007, moving to Maidenhead United in March 2008. He was an integral part of the Maidenhead side that narrowly avoided relegation at the end of the season, Tardif keeping four sheets in the final five games. He became a father shortly after the end of the season and chose to reduce the time spent travelling from his Portsmouth home by joining Farnborough in May 2008. He joined Bognor Regis Town in September 2008.
He returned to Maidenhead United in the summer of 2009.
On 2 June 2010, Tardif rejoined Basingstoke Town.. On the 26th of August 2010, Tardif had his Basingstoke Town contract terminated by mutual consent and returned to his home island, signing with St. Martin's A.C.
Since returning to Guernsey, Tardif has represented Guernsey in the 2011 Muratti Vase Final, losing on penalties to Jersey, and at the 2011 Island Games. Also, in 2011 Chris joined the newly formed Guernsey FC as their goalkeeper.