Jason Jarrett became Norwich's first signing of the 2005 close season when on June 22nd 2005, he ageed to join the Canaries on a Bosman free transfer from Wigan when his contract with the Latics expired on July 1st 2005. The powerful midfielder had played for Norwich boss Nigel Worthington at Blackpool. He had also played for Wrexham and Bury.

Jarrett mde his debut for Norwich on the opening day of the 2005/6 season as a substitute in the 1-1 draw with Coventry. He was loaned to Plymouth after he failed to make the City first team but returned in January 2006 to an injury-struck Carrow Road.

At the beginning of March 2006, it was reported that Jason had joined Preston on loan until the end of the season with a view to a permanent transfer afterwards. Norwich were paid £30,000 for the loan deal and it was announced on 11th May 2006 by Preston's chairman that the permanent transfer would go through for an undisclosed sum. Jarrett left Norwich "with a stinging parting shot for Canaries boss Nigel Worthington. Jarrett, 26, ended a wasted year as a Norwich City player by blasting Worthington and, like Simon Charlton less than a fortnight ago, claiming he had been unfairly treated." (Pink Un website - 12 May 2006). This transfer formally went through on 1st June 2006.

Unhappy at not being a first team regular, Jarrett was loaned out to Hull City for a month commencing 2nd November 2006 and made 3 appearances for them. He was loaned again in February 2007 to Leicester City. He was told by Preston boss Paul Simpson that he is not part of his immediate plans at Preston and has not featured for the promotion chasers since early September. His loan was extended at the end of February 2007 to the end of the season and on 23rd February, the Daily Star reported that Leicester City owner Milan Mandaric was targeting a £1.5m swoop to make Geoff Horsfield and Jason Jarrett's loan moves permanent.

Jarrett was placed on the transfer list at the end of the 2006/7 season.

He joined struggling QPR on loan on 1st October 2007 until 1st January 2007

Returning to Preston, he was loaned out again on 31st January 2008 joining Oldham Athletic.

On 27th January 2009, Jarrett joined Brighton and Hove Albion on a free transfer. Jarrett had only made 3 appearances for Preston during the 2008/9 season. Brighton boss Micky Adams told the club website: "I am sure Jason will prove an important addition. He can add another dimension to our midfield while bringing some experience to the squad."

Jarrett was one of 13 players released by Brighton's manager Russell Slade at the end of the 2008/9 season

He joined Port Vale on a short term contract at the end of September 2009. This lasted until the end of December. On 30th December 2009, Vale decided not to keep Jarrett any further.

In the summer of 2010, Jason trained with Bury before signing a a six-month contract after a successful trial period with Oldham on 23rd July 2010. Manager Paul Dickov told the club website: "We have a very young team and Jason's experience helps us."

He left Oldham on 13th January 2011 having made 8 appearances.

After playing for Airbus UK in Wales, Jarrett signed for Chester in May 2013. Chester were relegated from the Conference in April 2014.

In the summer of 2014, Jarrett moved to Salford City.