Ending weeks of speculation that his lengthy tenure as the Bengals' head coach was over, Lewis was signed to a two-year contract that runs through the 2019 season, the team announced Tuesday.
"Marvin Lewis has been an important member of the Cincinnati community and the Bengals family for the past 15 years, and we are happy to have reached this agreement," said Bengals president Mike Brown in a statement. "Marvin has made significant contributions during his time here. While recently we have fallen short of our expectations, we have full confidence in Marvin to re-establish winning football in 2018."
Although Lewis is the winningest coach in franchise history, posting a 125-112-3 record in his 15 seasons, Cincinnati has had back-to-back losing seasons following a run of four consecutive seasons with double-digit victories.
Talk of Lewis' demise picked up after the Bengals were steamrolled by Chicago and Minnesota by a combined 67-14 to extend their losing streak to three and drop their record to 5-9.
However, Cincinnati won its final two games and, at what was expected to be a farewell news conference on Monday, Lewis told the assembled media that he was in ongoing discussions with the club about his future.
"My family and I are very grateful for the opportunity to stay in Cincinnati and continue my career with the Bengals," said Lewis in a statement released by the club. "My job is to win a World Championship. We have a talented roster full of veteran leaders and emerging young stars, and I am committed to making the necessary improvements to put this team in the best position to win."
Cincinnati reached the postseason seven times under Lewis, including a run of five straight seasons from 2011-15, when the team won 52 games.
Lewis also guided the team to four AFC North titles, but the biggest knock against the 59-year-old coach was his lack of success in the playoffs, with the Bengals going 0-7 during his tenure.
Following a successful stint as the Baltimore Ravens defensive coordinator from 1996 to 2001, including a Super Bowl title in 2000, Lewis took over a Cincinnati franchise in shambles in 2003.
The Bengals had gone 2-14 in 2002, but Lewis led them to consecutive 8-8 marks before reaching the postseason with an 11-5 mark in 2005.
"To be one place for 15 years is a true testament to him," said quarterback Andy Dalton on Monday. "He's made a big impact on a lot of guys. He has provided stability."