Blackfalds RCMP say Justin Mueller, 28, telephoned police from a residence in Edmonton on Friday night.
Officer went to a home in the city and Mueller was taken into custody.
Police say a 20-year-old woman was leaving her job shortly early Thursday morning at a hotel in Red Deer, Alta., when a man came to her driver's side door and brandished a knife.
The male forced the female to get in the passenger seat and he drove to a bank where he took her to the ATM and forced her to withdraw money from her account.
RCMP say he then took her to a rural location near Penhold where he sexually assaulted her before driving her back to Red Deer and dropping her off at a convenience store and leaving with her vehicle.