Tampa Bay could not produce an offensive touchdown and was held to less than 200 yards by the Redskins, who were unbeaten in their four exhibition contests.
White, who is not expected to make the final roster, went 13-of-22 for 181 yards with an interception that was returned 37 yards for a score by Najee Goode. White also ran for a 7-yard touchdown with 1:09 left in the second quarter that gave Washington a 27-6 halftime lead.
Tampa Bay went 1-3 in the preseason. Rookie Mike Glennon saw most of the work at quarterback for the Bucs and completed 7-of-16 passes for 63 yards.
The Redskins will open the regular season by hosting Philadelphia in one of the two Monday night contests. Tampa Bay kicks off at the New York Jets in a Sunday game.