He made his competitive senior Blues debut on the wing in the 17-15 win over the Ospreys in August 2007 and has gone on to make 81 appearances for the region during his six seasons with the senior team, scoring 17 tries.
Roberts formed a formidable partnership with New Zealander Casey Laulala in the 65 games that the former All Black played for the Blues during his three years in the Welsh capital.
During his first year of senior rugby Roberts made his Wales debut on the wing against Scotland at the start of the 2008 Grand Slam season, going on to win 44 caps.
He was named as the British & Irish Lions Player of the Series on the 2009 tour of South Africa, where he partnered Brian O'Driscoll in the Lions midfield in the first two Tests.
He played two full games for the Blues during the 2011/12 season and played 15 games for Wales before a knee injury forced him out of action for six months before retuning to action against the Dragons in September.
A medical student at Cardiff University Jamie will sit his final exams during the 2013 Six Nations tournament.
Cardiff Blues Chief Executive Richard Holland said,
"The offer that we made to Jamie was an extremely attractive one and would have seen him become certainly the highest paid player in the Blues squad, and arguably in the UK."
"As a business we simply don't have the resource to compete with the offers that Jamie has received."
"Naturally we are disappointed that Jamie has decided to leave the region but we wish him the best of luck with his career."
"Given news of Jamie's departure we will begin the search to find a suitable marquee player who will be eligible to play for us throughout the entire season."
Cardiff Blues Chairman Peter Thomas added,
"We have invested a lot of time, money and effort developing Jamie as a rugby player from an early age after identifying him as a star of the future."
"We have stuck by him through thick and thin and supported him during last season when he only completed two matches for the Blues because of his knee injury and international duties, playing 15 matches for Wales."
"It is impossible for the Welsh regions to compete with the kind of money that is on offer from other clubs in other countries."
"The time has come that the Welsh benefactors should not be responsible for funding the professional game."
"The chairman of the regions can guide companies but if we want to keep Jamie Roberts and other international players in Wales then the governing body has to intervene."
"The player drain out of Wales, which has a negative impact on the Welsh regions and the national team, will only continue without increased funding from the governing body."
"As an example with our recent game against Leinster, the IRFU pay for fourteen of their players and additionally fund the province for the remaining players in excess of 4 million euros. Compared to the cost of the Cardiff Blues squad that's almost double."
"You'll never win the Heineken Cup with that margin to compete with."
"The governing body has to take far more responsibility."