Catawba College Tomsula began his coaching career as a strength and conditioning coach at Catawba College in 1989. After serving as an assistant coach at Charleston Southern under defensive coordinator Fred Hamilton from 1992 to 1995, Tomsula returned to Catawba College, where he was a member of the coaching staff until 2005 and helped lead the Catawba Indians to four
South Atlantic Conference Championships. Tomsula was inducted into the
Catawba College Sports Hall of Fame 2015. During the 2010 season, Tomsula was named interim head coach for the regular-season finale against the
Arizona Cardinals after head coach
Mike Singletary was fired. Tomsula won his head coaching debut 38–7. For the 2011 season, incoming new head coach
Jim Harbaugh retained Tomsula in his previous position as defensive line coach, where Tomsula remained through all four seasons of the Harbaugh era.
Head coach On January 14, 2015, Tomsula became the 49ers' head coach, succeeding Jim Harbaugh, who had been fired by 49ers CEO
Jed York. Tomsula employed new coaching practices, which included giving his players breaks to check social media during meetings, shorter and easier practices, and more days off. The result was one of the worst offenses in team history. Scoring only 238 points, the 49ers struggled to a 5–11 season, with quarterback
Colin Kaepernick ending the season on injured reserve after being benched. On January 3, 2016, Tomsula was fired just a few hours after the regular-season finale against the
St. Louis Rams, which the 49ers won 19–16 in overtime. A few days later, York confirmed that the 49ers would pay Tomsula $14 million for his lone season as head coach.
Washington Redskins On January 23, 2017, Tomsula was hired as defensive line coach for the
Washington Redskins. In 2020, with the hiring of new head coach
Ron Rivera, Tomsula was free to find a job elsewhere.
Dallas Cowboys On January 8, 2020, Tomsula was hired as the defensive line coach for the
Dallas Cowboys. He reunited with defensive coordinator
Mike Nolan who was his head coach with the
San Francisco 49ers. Tomsula faced heavy restrictions due to the
COVID-19 pandemic in terms of physical contact with the players, their availability due to a positive test for
COVID-19 or having been exposed to someone who had it, a reduced
training camp schedule and the cancellation of preseason games, which made it difficult to implement the new defensive scheme. To make matters worse, most of the free agent signings for the defense were ineffective. The team would finish with a losing record (6-10), while the defensive unit allowed the most points in franchise history (473), finishing 31st in the league in run defense (158.8 YPG), 28th in scoring defense (29.6 PPG) and 20th in sacks (31). On January 8, 2021, he was fired along with defensive coordinator Nolan.
Rhein Fire In the 2022 preseason, the management of the new
Rhein Fire announced that Tomsula would be the first head coach for the upcoming season of the
European League of Football. In their inaugural season, Tomsula coached the expansion Rhein Fire to a 7–5 record, the second best in the Southern Conference though the team failed to qualify for the playoffs. In 2023, Rhein finished the regular season 12–0, and Tomsula earned a nomination for Coach of the Year. Tomsula did not return as the Fire coach in 2025. ==Head coaching record==