The terms of Koetter's contract were being finalized Thursday night, a source told ESPN. The team said it will have a news conference to announce the new hire at 2 p.m. ET Friday.
"Dirk has established himself as one of the top offensive coaches in our game while enjoying success at every stop during his college and NFL career," Buccaneers co-chairman Joel Glazer said in a statement. "His success with our offense last season, along with his familiarity with our players and our organization, makes Dirk the right man to lead our team moving forward."
Koetter, who interviewed with general manager Jason Licht and ownership Tuesday, replaces Lovie Smith, who was fired Jan. 6.
Koetter also interviewed with the San Francisco 49ers to replace the fired Jim Tomsula. The Miami Dolphins and Philadelphia Eagles also requested permission from the Bucs to interview Koetter for their top vacancies, but the Dolphins chose Adam Gase and the Eagles chose Doug Pederson.
"When I started this search for a new head coach, the focus was on finding someone that could be a strong leader as well as a consummate teacher, and Dirk is both," Licht said in a statement. "He brings the passion and drive that will re-energize our organization and help us establish the winning culture that will help us become the championship-caliber team that our fans deserve."
While Koetter's specialty is offense, the Bucs' top priority this offseason will be fixing a defense that has had difficulty keeping opponents out of the end zone.
The Bucs improved from 25th to 10th in yards allowed this season; however, they were 26th in scoring defense, yielding 26 points per game.
Former Falcons head coach Mike Smith will serve as Koetter's defensive coordinator.
Koetter has been an NFL offensive coordinator since 2007, but this will be his first head-coaching job in the league. He was the coach at Boise State from 1998 to 2000 and at Arizona State from 2001 to '06, before moving on to the NFL.
He joined the Tampa Bay staff in 2015 and helped guideJameis Winston to one of the best seasons by a rookie quarterback in NFL history. Winston completed 58.3 percent of his passes for 4,042 yards with 22 touchdowns and 15 interceptions, becoming just the third rookie QB to surpass 4,000 yards; the others wereCam Newton and Andrew Luck.
The Buccaneers' offense ranked fifth in rushing, thanks to Doug Martin's 1,402 yards, which ranked second in the league. They were also 17th in passing and fifth overall after being 30th in the league in 2014.
During a news conference the day after the team announced Smith's firing, Licht said the work Koetter did with Winston made him a strong candidate to fill the vacancy.
"I think any coordinator, quarterback coach in that role with a quarterback, particularly Jameis, a young quarterback, that's an important bond. That's a strong bond that they need to have," Licht said. "That was present."
Koetter had similar success with QBs as an offensive coordinator with the Jacksonville Jaguars and Atlanta Falcons. Koetter spent 2010 to '12 in Atlanta, and quarterback Matt Ryan posted the top three passing yardage totals in Falcons history in those three years. Ryan set a franchise record with 4,719 yards and 32 touchdowns in Koetter's final season. Koetter was let go by the Falcons when coach Mike Smith was fired after the 2014 season.
Koetter spent five seasons in Jacksonville (2007-11) and helped then-quarterback David Garrard post one of the best seasons in team history. Garrard threw 18 touchdown passes and only three interceptions in 2007. He threw what was then a franchise-record 23 touchdown passes in 2008.
Information from ESPN's Michael DiRocco, Jeremy Fowler and The Associated Press was used in this report.
Bucs will name Dirk Koetter coach
Adam Schefter breaks down Tampa Bay's decision to promote Dirk Koetter from offensive coordinator to head coach.