Initially serving as a backup, Tannehill became the starter midway through the season and led the team to the AFC Championship Game.

[1] He attended Big Spring High School, where he played football and basketball, and ran on the track and field team.

[4] Tannehill redshirted his first season (2007) at Texas A&M after turning down offers from the University of Houston, TCU, Tulsa, and UTEP.

[29] On July 28, 2012, Tannehill signed his four-year rookie contract with the Dolphins worth about $12.688 million, with a fifth-year option.

[39] In Week 16, Tannehill set a franchise record for longest run by a quarterback by rushing 31 yards in a single play.

During that game against the Buffalo Bills, Tannehill also became the fifth quarterback in team history to surpass 3,000 passing yards in a season.

[42] In the next game, Tannehill went 23 of 34 for 319 yards for a touchdown, but he was sacked five times and lost a fumble in the 24–20 road victory against the Indianapolis Colts.

[44] Tannehill struggled in Week 4 against the New Orleans Saints, going 22 of 35 for 249 yards and a touchdown, but also committed four team turnovers as he was intercepted thrice and lost a fumble.

[48] In the next game against the Cincinnati Bengals, Tannehill went 20 of 28 for 208 yards along with a 1-yard touchdown run despite being sacked six times due to the tottering offensive line in the 22–20 overtime victory.

[49] During Week 10 against the Tampa Bay Buccaneers, Tannehill went 27 of 42 for 229 yards while throwing two touchdowns, one interception, and two sacks in the 22–19 road loss.

[50] In the next game against the San Diego Chargers, Tannehill completed 22 of 35 pass attempts for 268 yards, a touchdown, and an interception in a 20–16 win, despite being sacked four times.

[51] During Week 14 against the Pittsburgh Steelers, Tannehill completed 20 of his 33 attempts with three touchdowns, one interception, and two sacks in a 34–28 road victory.

[53] During Week 16 against the Bills, Tannehill followed up his best game with a lackluster performance going 10 of 27 for 82 yards and was sacked seven times in the 19–0 road loss.

However, during the 2014 offseason, the Dolphins hired new offensive coordinator Bill Lazor giving Tannehill a new playbook to learn for the first time since high school.

In the penultimate game of the regular season against the Minnesota Vikings, Tannehill had a season-high 396 passing yards, four touchdowns, and one interception in the 37–35 victory.

[61][62] On May 18, 2015, Tannehill signed a six-year, $96 million contract extension with the Dolphins through the 2020 season, making him an unrestricted free agent in 2021.

[63][64] During a Week 7 victory over Texans, Tannehill became the 64th quarterback in NFL history to post a perfect 158.3 passer rating.

)[66] Tannehill then had a rough spell during a Thursday Night game against the Patriots, throwing no touchdowns and 2 interceptions in a 36–7 loss.

[67] and in three successive games against the Patriots, Bills[68] and Philadelphia Eagles[69] fumbled one ball in the end zone for an opposition safety.

[citation needed] On December 15, he threw for 236 yards and one touchdown in the Dolphins' 31–24 loss to the New York Giants on Monday Night Football.

[73] Tannehill played in 13 games, missing the last three due to an injury he suffered against the Cardinals where a low hit by Calais Campbell resulted in a partially torn anterior cruciate ligament in his left knee.

On August 3, 2017, Tannehill suffered an injury to his left leg when it buckled in the team's first non-contact 11-on-11 practice of season.

[80] On August 6, the team signed recently retired quarterback Jay Cutler to act as Tannehill's replacement.

[84] On March 1, 2018, head coach Adam Gase announced that Tannehill would continue to be the starting quarterback for the Dolphins.

[100] In the regular-season finale against the Texans, he threw for 198 yards and two touchdowns in the 35–14 road victory, taking the Titans to the playoffs as a Wild Card team.

[109] Tannehill was named to his first career Pro Bowl on January 20, 2020, replacing the Super Bowl-bound Patrick Mahomes.

[135] During that span, Levis filled in as the starter and led the team to a 28–23 win over the Falcons in his first start, but lost to the Steelers 20–16 in Week 9.

[136][137] In Week 10, head coach Mike Vrabel announced that Levis would be the Titans starting quarterback moving forward and that Tannehill would be his backup.

[138] Tannehill started two of the Titans' last three games due to injuries to Levis, including a 28–20 Week 18 win where he passed for 168 yards and 2 touchdowns to eliminate the rival Jaguars from the playoffs.

[146] Tannehill graduated with a bachelor's degree in biology in May 2011[147] and had planned to become an orthopedic surgeon specializing in knee injuries.