The 2015 season was the Cincinnati Bengals' 46th in the National Football League (NFL), their 48th overall and their 13th under head coach Marvin Lewis.

The Cincinnati Bengals got off to a franchise best start after beating the Pittsburgh Steelers at Heinz Field by a score of 16–10, improving them to 7–0.

They did not return to the postseason nor had a winning record until 2021, where they reached Super Bowl LVI, although they lost to the Los Angeles Rams.

After the break, the Bengals went back to work as Dalton and Eifert hooked up again this time on an 8-yard TD pass (with a failed PAT) for a 30–0 lead.

In the fourth quarter, it was all Raiders when Backup QB Matt McGloin found Marcel Reese on 2 straight TD passes: from 11 and 9 yards out (with a failed 2-point conversion) for a final score of 33–13.

The Bengals moved ahead by 8 when Andy Dalton found Marvin Jones on a 45-yard pass for a 14–6 game at halftime.

The Ravens were able to get on the board in the third quarter when Joe Flacco found Steve Smith Sr. on a 50-yard TD pass for a 14–7 game and the only score of the period.

The Bengals however got back to work in the third quarter when Andy Dalton found Brandon Tate on a 55-yard TD pass increasing their lead to 21–12.

The Seahawks scored 24 straight points: later on in the quarter they managed to tie it up when Russel Wilson found Jermaine Kearse on a 30-yard TD pass for a 7–7 game.

In the second quarter, the Seahawks took the lead as Steven Hauschka nailed a 24-yard field goal for a 10–7 game at halftime.

Despite the return of Ben Roethlisberger, the Bengals managed to come from behind and win the game 16–10 and achieve a mark of 7–0 for the first time in franchise history.

Tight end Tyler Eifert caught three touchdown passes from Andy Dalton in the game, as he tied the team record for TDs in a season by a TE (9).

The Texans' starting quarterback, Brian Hoyer, left the game with a concussion, but recently signed backup T. J. Yates threw a fourth-quarter touchdown pass to DeAndre Hopkins.

With the loss, the Bengals dropped to 8–1, and were no longer undefeated, leaving the New England Patriots as the only unbeaten team in the AFC at that point.

In the first quarter, the Bengals would strike first as Dalton found Tyler Eifert on a 3-yard touchdown pass to give them a 7–0 lead for the only score of the period.

However, the Bengals would make the game close once again, as Eifert caught his second touchdown of the night, cutting the lead to 31–28.

The most notable part of this drive, and, perhaps, the game, was an unsportsmanlike conduct penalty by Bengals defensive tackle Domata Peko.

With a Pittsburgh to loss to Seattle later that evening, the Bengals re-gained a 3-game lead in the AFC North Division.

Due to the Steelers' loss to the Ravens the previous day, the Bengals entered the game as the AFC North champions.

In the second half, momentum shifted mightily after a missed field goal by Mike Nugent in the third.

Emmanuel Sanders hauled in an 8-yard pass from Brock Osweiler to cut the deficit to 14–10, and Denver claimed the lead for the first time in the game on a 39-yard touchdown run by C. J. Anderson with 11:17 remaining in the 4th Quarter.

The tired Bengals failed to put any points on the board in the extra period, allowing a 37-yard McManus field goal to make the score 20–17 Denver.

A botched snap on the ensuing Bengals drive was recovered by the Broncos, ending the game and Cincinnati's hopes for a first-round bye in the playoffs.

Cincinnati returned home to Paul Brown Stadium to face the AFC North rival Baltimore Ravens in the final game of the NFL regular season.

After offensive struggles by both teams during the opening quarter, the Ravens got on the board with a 28-yard field goal by Justin Tucker.

With 1:56 remaining in the first half, Tyler Eifert, back after missing two games due to injury, caught a 22-yard pass from McCarron as the Bengals took the lead, 7–6.

Baltimore would later retake the lead, 9–7, as time expired in the half with a third Tucker field goal from 49 yards.

Cincinnati came out strong in the second half, scoring 17 unanswered points en route to the 24–16 victory.

A. J. McCarron tried to go for a miracle with 0:06 left in the game, but it fell incomplete, leading to the Bengals being one-and-done for the fifth season in a row and dropping their overall record to 12–5.