Lewis was entering the final year of a previous two-year extension.
The 53-year-old Lewis guided the Bengals to a 9-7 record in 2011. They lost to
the Houston Texans in the first round of the playoffs.
Lewis has been the coach of the Bengals since 2003, compiling an overall
record of 69-77-1 during that span. He has led Cincinnati to the playoffs in
two of the last three seasons, and to three postseasons overall.
The Bengals have won two AFC North titles under Lewis.