He played college football for the Notre Dame Fighting Irish and was selected by the Steelers in the second round of the 2014 NFL draft.

In his sophomore season, Tuitt earned a starting position and recorded 42 tackles, including 13 for loss, 12 sacks, 9 quarterback hurries, and 3 forced fumbles.

[2] As a junior in 2013, after dealing with the effects from off-season hernia surgery,[3] he totaled 49 tackles, including 9 for a loss, 7.5 sacks, a forced fumble, and an interception return for a touchdown against Michigan.

Tomlin flew to South Bend specifically to meet with Tuitt, although he was unable to perform physically after having surgery on his foot the previous week.

[11] He entered training camp his rookie year, competing with Cameron Heyward, Brett Kiesel, and Cam Thomas for a starting defensive end position.

In Week 16, Tuitt collected a season-high three solo tackles and made his first career sack on Kansas City Chiefs quarterback Alex Smith.

Tuitt entered training camp competing for the vacant starting defensive end position left by the retirement of Brett Kiesel.

He was named a starting defensive end to begin the season, after beating out teammates Cam Thomas, Leterrius Walton, Clifton Geathers, Caushaud Lyons, and Joe Kruger.

The next game, Tuitt made four combined tackles and 1.5 sacks on San Francisco 49ers quarterback Colin Kaepernick, helping the Steelers win, 43–18.

The following week, Tuitt made a career-high ten solo tackles and sacked Ravens' quarterback Joe Flacco during the Steelers' 20–23 loss.

During a Week 14 matchup against the Bengals, Tuitt recorded his first career interception off a shovel pass from quarterback Andy Dalton.

On November 13, 2016, Tuitt racked up three combined tackles and sacked Dallas Cowboys quarterback Dak Prescott for his first of the season, as the Steelers lost, 35–30.

[19] Tuitt received an overall grade of 82.0 from Pro Football Focus and was ranked 21st among all qualified interior defensive linemen in 2016.

[21][11] Tuitt and Cameron Heyward returned as the Steelers' starting defensive end duo to begin the regular season.

He started the Steelers' season-opening 21–18 victory over the Browns, but left after suffering an injury on the second play of the game and finished with only one tackle.

[25] In week 10 against the Carolina Panthers, Tuitt hyper extended his elbow and missed the next two games against the Jaguars and Broncos.

[41] While coping with the death of his brother and dealing with a lingering knee injury, he did not play in a single game during the 2021 season[42] On June 1, 2022, Tuitt announced his retirement from professional football.

[43] [44] On June 2, 2021, Tuitt's younger brother, Richard Bartlett III, was killed in a hit and run in Johns Creek, Georgia.