The Baseball Writers' Association of America announced the finalists Monday. Voting was completed before the postseason, and award winners will be announced next week on MLB Network.
A season after he was the NL Rookie of the Year, Bryant hit 39 home runs with 102 RBIs while batting .292. The third baseman also scored a league-high 121 runs.
Detroit's Michael Fulmer, the Yankees' Gary Sanchez and Cleveland's Tyler Naquin are finalists for AL Rookie of the Year. Seager, Dodgers teammate Kenta Maeda and Washington's Trea Turner are the NL contenders, with the top rookies being announced next Monday.
Maddon, Washington's Dusty Baker, and Dave Roberts of the Dodgers are up for NL Manager of the Year. Cleveland's Terry Francona, who guided his team into the World Series, Texas' Jeff Banister and Baltimore's Buck Showalter are the AL candidates. Those honors will be awarded Nov. 15.
The Cubs led the majors with 103 wins during the regular season.
Last year, Chicago won three major awards after reaching the NL Championship Series. In addition to Bryant earning rookie honors, Maddon was the NL Manager of the Year and pitcher Jake Arrieta took home the NL Cy Young Award.