Halldorson had seven career wins on the Canadian Tour and its predecessors.

He won the unofficial Deposit Guaranty Golf Classic in 1986.

Halldorson played briefly on the Champions Tour after turning 50 in 2002.

He operated a golf course design business with fellow former PGA Tour golfer Mike Morley.

[3] PGA Tour playoff record (0–1) Note: Halldorson never played in The Open Championship.