The 32-year-old Carter, who will join French side Racing Metro at the conclusion of this year's World Cup, had played mostly at inside centre last year when he returned to the Crusaders from a sabbatical to accommodate Slade's good form.
The fact he will play in his preferred fly-half position suggests he will get the nod from coach Todd Blackadder to start there for the Crusaders' opening game against the Melbourne Rebels on Feb. 13 in Christchurch.
Slade and tighthead prop Owen Franks will also be making their first appearance for the Crusaders in 2015 after they had an extended break due to All Blacks' duties.
Carter, who barely played at all in 2013, opted to join the team as early as possible for pre-season training as he begins what is likely to be his last year in New Zealand rugby.
The Crusaders' first match dovetails with the opening of the cricket World Cup, which begins on Feb. 14 with a match between co-hosts New Zealand and Sri Lanka at Hagley Oval in Christchurch.