He played college football for the UCF Knights, where he received AAC Offensive Player of the Year honors as a junior and was MVP of the 2014 Fiesta Bowl.

After being released by the Jaguars in 2018, he spent his final three seasons as a backup for the Los Angeles Rams, Denver Broncos, Green Bay Packers, and New Orleans Saints.

[22] During Week 3, Bortles made his NFL debut when he came in relief of Chad Henne in the second half of a 44–17 blowout loss to the Indianapolis Colts.

[27] Two weeks later against the Tennessee Titans, he produced 336 yards on 32-of-46 passes (three franchise rookie records), but the Jaguars lost 14–16 due to a blocked field goal.

[31] Bortles established himself as a dual-threat quarterback in his rookie season by rushing for 20 or more yards seven times in 2014, second only to Russell Wilson of the Seattle Seahawks.

[33][34] Bortles, after having a strong preseason in his second year, started the 2015 season slow with a touchdown and two interceptions in the season-opening 20–9 loss to the Carolina Panthers.

[37] During Week 13, he broke the Jaguars single game record with five touchdown passes in a 42–39 road loss to the Titans.

After throwing no touchdowns in the regular season finale, he shared second place with Eli Manning, Cam Newton, and Carson Palmer, behind only Tom Brady's 36.

He was also seventh in the NFL in passing yards with 4,428, behind Drew Brees, Philip Rivers, Brady, Palmer, Matt Ryan, and Manning.

The following week, Bortles caught his first career reception from wide receiver Marqise Lee on a 20-yard trick play that netted a touchdown and led to a Christmas Eve 38–17 victory over the Titans.

[54] Despite the loss, the Jaguars clinched the AFC South due to the Titans losing to the Los Angeles Rams.

[55] Bortles finished the regular season with 3,687 passing yards, 21 touchdowns to 13 interceptions, and an 84.7 quarterback rating (21st of 35 players with at least 200 attempts).

[57] In the Wild Card Round, the Jaguars defeated the Buffalo Bills by a score of 10–3 in Bortles's first playoff game.

[60] Due to his poor passing performance against the Bills, Bortles received heavy criticism from analysts and even other players in the league.

"[61][62] However, Bortles bounced back in the Divisional Round, leading the Jaguars to beat the heavily favored Pittsburgh Steelers on the road by a score of 45–42.

[63] This would be Jacksonville's first AFC Championship game appearance since 1999, but they lost to the New England Patriots on the road by a score of 24–20 after spoiling a 20–10 lead in the fourth quarter.

[70] The following week against the Dallas Cowboys, Bortles threw for 149 yards, a touchdown, and an interception to Jeff Heath in triple coverage in a 40–7 road loss.

Bortles was benched for Cody Kessler after he lost the second fumble, finishing the day with a career-low 61 yards on 12 attempts.

Nevertheless, head coach Doug Marrone elected to leave Bortles as the starter for the Week 8 matchup in London against the Philadelphia Eagles.

He led the Jaguars on three straight scoring drives late in the game to draw within six points before completing just two of his last nine passes in the 18–24 loss.

[77] The next day, Marrone announced that Bortles would be benched in favor of Cody Kessler for the Week 13 matchup against the Colts.

[79] In Week 16 against the Dolphins, Bortles entered the game in relief of a struggling Kessler in the late second quarter, was promptly sacked on third down, benched, then reentered the game in the late third quarter where he completed five of six passes for 39 yards and rushed four times for 26 yards to help lead the Jaguars to a 17–7 victory.

[85] Over his five years with the Jaguars, Bortles led the league in interceptions (75 in 75 games, a league-leading 13 of which were returned for touchdowns) and second among quarterbacks in fumbles (46) to Russell Wilson.

[87] Bortles played three snaps of a Week 7 blowout of the Atlanta Falcons with a 20-point lead late in the fourth quarter.

[93] On November 28, 2020, Bortles was placed on the practice squad/COVID-19 list after coming in close contact with Jeff Driskel, who tested positive for the virus.

[96] On December 29, 2020, Bortles was signed by the Rams off the Broncos' practice squad following an injury to starter Jared Goff.

[99] On November 4, 2021, Bortles was re-signed to the Packers practice squad as the backup for Jordan Love after starter Aaron Rodgers was unavailable for Week 9 due to a COVID-19 diagnosis.

[102] On December 24, 2021, Bortles was signed by the New Orleans Saints to back up rookie quarterback Ian Book after starter Jameis Winston tore his ACL in week 8.

[105] On April 5, the Saints waived Bortles, who had asked to be released from his contract following the team's decision to sign Andy Dalton.