Boeing will supply the four pre-owned Boeing 767-300ER aircraft that WestJet expects to begin receiving next summer.
The airline, which confirms Boeing as the 767 supplier during its second quarter earnings call on 29 July, declines to say which airline previously operated the aircraft.
But executives do confirm the 767s will be equipped with winglets and have 262 seats, including premium economy seats.
The aircraft will also be "completely refurbished" with "modern interiors" and be fitted with "our newest inflight entertainment system," says WestJet.
Executives add that the company has not yet "made the final determination" as to whether the company will purchase or lease the aircraft from Boeing.
The first 767 is expected to be delivered and enter revenue service next summer, but the aircraft will first operate overland routes for 90 days until being certified for extended-range twin operations (ETOPS).
By late 2015, the airline expects to begin deploying two of the 767s on flights to Hawaii from Edmonton and Calgary, routes currently operated for WestJet by Thomas Cook using 211-seat Boeing 757-200s.
WestJet executives say they have "absolutely no trepidation" in their ability to fill seats on the 767s, noting "very high load factors" on the existing 757s to Hawaii.
The first of WestJet's 767 pilots will be check airmen and will begin training between February and April next year, and other pilots will begin training a few months later.