43-year-old Brady, who previously earned MVP honours with New England Patriots, completed 21 of his 29 passes for 201 yards and three touchdowns in the win and joined Peyton Manning as the only starting quarterbacks to win Super Bowls with multiple teams.
Making his 10th Super Bowl appearance, Brady claimed his seventh ring on Sunday, wasting no time putting the Bucs in position for their second title and first since the 2002 season by firing for three first-half touchdowns and a 21-6 halftime lead.
The early onslaught included a final-minute drive capped with a one-yard strike to Antonio Brown with six seconds left. Former Pats teammate Rob Gronkowski grabbed two touchdowns, padding the postseason record for scoring connections from Brady to 14. Gronkowski had six grabs for 67 yards.
A 27-yard TD run in the third quarter by Leonard Fournette, who recorded 89 yards on 16 touches, made it 28-9. That TD helped ice the outcome as the Bucs constantly pressured the Chiefs' Patrick Mahomes, who suffered his worst NFL defeat.
Defending champions Kansas City settled for three field goals by Harrison Butker.
Mahomes finished just 26 of 49 for 270 yards. He had two interceptions, a pick by Antoine Winfield that led to a third-quarter Tampa Bay field goal, and the second with a minute remaining by Devin White.
Mahomes scrambled for 33 yards, Travis Kelce led the Chiefs with 10 receptions for 133 yards, and the Chiefs committed 11 penalties, eight in the first half.
Here's a full match report, including a streaker!