Ferrari impressed in pre-season testing while much is also expected at Red Bull where Vettel is hoping to go one better after finishing runner-up to Button in last season's championship race.
It means the British team will head to the first of four winter sessions at Circuit Ricardo Tormo in Valencia between 1-3 February with a standard 2010 chassis and a limited number of updates, while rivals Red Bull and Ferrari will unveil their new models for on-track testing.