John Turner was a member of neither the House of Commons or the Senate during his entire term as Prime Minister.
Three provinces—New Brunswick, Newfoundland and Labrador, and Prince Edward Island—have never been represented by a sitting prime minister.
Mackenzie King briefly represented the Prince Edward Island riding of Prince, and Jean Chrétien even more briefly represented the New Brunswick riding of Beauséjour prior to their assuming the premiership, however.
Both King and John Diefenbaker served Prince Albert; and both Wilfrid Laurier and Louis St. Laurent represented Quebec East.
Similarly, John A. Macdonald served his fourth term as MP for Carleton, a riding represented by Robert Borden as Opposition Leader in the 10th Parliament.