The Steelers will send a 2019 fifth-round pick to Oakland in the deal, Raiders coach Jon Gruden said.
Pittsburgh released WR Justin Thomas in a corresponding move.
Switzer, a fourth-round pick by the Cowboys in 2017 who has been traded twice in the past 121 days, finished his rookie year with six catches for 41 yards.
The Steelers need help in the return game, and Switzer has experience in that area. Last year, Switzer posted 256 punt return yards and one touchdown on 29 tries (8.8 yards per attempt, ranking 12th in the league), along with 600 kickoff return yards on 24 tries (25 yards per attempt, third leaguewide).
Steelers punt returner Cam Sutton fumbled on his first attempt Saturday against the Titans. Running back Fitz Toussaint handled the first kickoff of the game but is not a lock to make the team. Switzer also provides slot receiver depth, but the Steelers are in decent shape there with JuJu Smith-Schuster as an inside-out weapon and Eli Rogers returning soon from a torn anterior cruciate ligament.
This is the second trade between the Steelers and Raiders this offseason. During the draft, Oakland acquired receiver Martavis Bryant for a third-round pick.