Former Premier Mike Rann retires from politics today, closing the curtain on a 26 year career.

Mr Rann steps away from politics today after 22 years on the frontbench, 17 as Labor leader and more than nine as Premier.

He was first elected to parliament in 1985, before becomning premier in 2002.

Mr Rann was forced from the top job by his party and relinquished the premiership to his deputy, Jay Weatherill, in October last year.

From today his focus will be on his wife Sasha who is battling breast cancer.

A by-election will be held in his seat of Ramsay on February 11, the same day as voters go to the polls in former treasurer Kevin Foley's seat of Port Adelaide