Baker Reagan Mayfield (born April 14, 1995) is an American professional football quarterback for the Tampa Bay Buccaneers of the National Football League (NFL). Following one season of college football with the Texas Tech Red Raiders, he played for the Oklahoma Sooners, becoming the first walk-on player to win the Heisman Trophy. He was selected first overall by the Cleveland Browns in the 2018 NFL draft.

Mayfield set the NFL rookie quarterback record for passing touchdowns during his first year, along with ending a 19-game winless streak for the Browns in his debut. His most successful season with the team was in 2020 when he led the Browns to their first playoff appearance since 2002 and first playoff victory since 1994. Following a performance decline and conflict with Browns management, Mayfield was traded from Cleveland in 2022, spending the year with the Carolina Panthers and Los Angeles Rams.

In 2023, Mayfield joined the Buccaneers, leading the team to two consecutive division titles and a playoff victory. He also earned two consecutive Pro Bowl selections. Mayfield is currently the all-time leader in playoff passer rating.

Baker Reagan Mayfield was born on April 14, 1995, in Austin, Texas, to James and Gina Mayfield as the younger of two sons. James, a private equity consultant, encountered financial difficulties during his younger son's senior year in high school. These struggles forced the Mayfields to sell their home and live in rental homes. Mayfield was given his distinctive name, Baker, which was his mother's idea, under the condition by his father that he also be named after the 40th U.S. President Ronald Reagan, which became his middle name.

Mayfield grew up as a fan of the University of Oklahoma; he attended a number of their games during his childhood. His father played football for three years at the University of Houston, though he never lettered.

Mayfield was the starting quarterback for the Lake Travis High School Cavaliers football team in Austin. He led Lake Travis to a 25–2 record in two seasons and won the 2011 4A State Championship. He finished his high school football career totaling 6,255 passing yards, 67 touchdowns, and eight interceptions. He was offered scholarships by Washington State, Rice, New Mexico and Florida Atlantic. Mayfield said "I easily could've gone to a place like Florida Atlantic, but my dad pushed me to realize that my dream was to play somewhere big." He chose to go to Texas Tech, where he was a walk-on.

Shortly before the start of the 2013 season, Mayfield was named as the starting quarterback following a back injury to projected starter and former Lake Travis quarterback Michael Brewer. Mayfield was the first walk-on true freshman quarterback to start an FBS season opener at the quarterback position.

In his first start against SMU, Mayfield passed for 413 yards and four touchdowns. His 43 completions of 60 attempts broke a school record held by Billy Joe Tolliver, and fell only four completions short of the NCAA Division I FBS single-game record for completions by a freshman, held by Luke McCown. For his performance, Mayfield was named Big 12 Conference Offensive Player of the Week – the first freshman Texas Tech quarterback to be named so since former Red Raider head coach Kliff Kingsbury in 1999. The game featured the last four former Lake Travis quarterbacks combined on both teams: Garrett Gilbert, Michael Brewer, Collin Lagasse, and Mayfield.