at the 2019 canadian championships, nadeau placed seventh in the short program after singling his triple axel attempt and receiving a negative grade of execution on his quadruple toe loop. he rallied in the free skate, where he placed fourth, and moved up to sixth place overall. nadeau called it "an even better program than what i expected, but it had to compensate for the short." while he finished sixth overall, three of the skaters who finished ahead of him (stephen gogolev, joseph phan and conrad orzel) were ineligible to compete as seniors due to either their age or a lack of the required minimum technical scores, and consequently nadeau was named to canada's team for the 2019 four continents championships, when he finished eleventh.