QB Josh Allen, No. 17 - Signed a six-year extension after setting a single-season franchise records for passing touchdowns (37), completions (396), 300-yard games (8), passer rating (107.2), completion percentage (69.2), passing yards (4,544), and total touchdowns (46) in 2020.

QB Mitchell Trubisky, No. 10 – The No. 2 pick in 2017 reached the playoffs twice in four seasons with Chicago before joining the Bills on a one-year deal during the offseason.

RB Zack Moss, No. 20 – The second-year running back caught a touchdown pass from Josh Allen in Buffalo's preseason finale against Green Bay.

RB Matt Breida, No. 22 – Fleet-of-foot running back signed a one-year deal during the offseason after averaging 4.9 yards per carry in four seasons with San Francisco and Miami.

RB Taiwan Jones, No. 25 – Veteran back has returned 82 kickoffs for 1,890 yards in his career.

RB Devin Singletary, No. 26 – The third-year running back rushed for 687 yards on 156 carries and caught 38 passes for 269 yards in 2020.

FB Reggie Gilliam, No. 41 – Rushed for two touchdowns during Buffalo's preseason win over Chicago.

WR Emmanuel Sanders, No. 1 – Veteran newcomer ranks eighth in the NFL with 8,619 receiving yards since 2010.

WR Marquez Stevenson, No. 5 – Rookie returned a punt 79 yards for a touchdown during the preseason win over Chicago.

WR Cole Beasley, No. 11 – Named a Second-Team All-Pro in 2020, when he set career highs in receiving yards (967) and receptions (82).

WR Gabriel Davis, No. 13 – Fourth-round pick made an impact as a rookie in 2020, catching seven touchdowns during the regular season before amassing 85 receiving yards in Buffalo's Wild Card game against Indianapolis.

WR Stefon Diggs, No. 14 - Named a First-Team All-Pro in 2020 after becoming the first player in Bills history to lead the NFL in catches (127) and yards (1,535).

WR Jake Kumerow, No. 15 – Caught a touchdown on his first NFL reception in 2020 during Buffalo's win over Denver.

WR Isaiah McKenzie, No. 19 – Versatile offensive weapons scored touchdowns as a receiver, a returner, and as a passer in 2020.

TE Dawson Knox, No. 88 – Recorded three touchdowns in 2020, his second NFL season.

TE Tommy Sweeney, No. 89 – Appeared in six games as a rookie in 2019 before missing last season with myocarditis resulting from COVID-19.

C Mitch Morse, No. 60 – Veteran has started 86-of-86 career games played, including seven playoff appearances.

OG Ike Boettger, No. 65 – Appeared in a career-high 12 games during the 2020 regular season, including seven starts at left guard, before starting all three of Buffalo's playoff games.

OL Ryan Bates, No. 71 – Returns for a third season in a reserve role on the Buffalo offensive line.

OT Tommy Doyle, No. 72 – The Bills drafted Doyle in the fifth round (161st overall) after he earned First-Team All-MAAC honors during a shortened senior season at the University of Miami (OH).

OL Daryl Williams, No. 75 – Signed a three-year contract extension after starting all 16 games at right tackle in 2020.

OT Dion Dawkins, No. 73 – The left tackle has not missed a game in four NFL seasons.

OL Cody Ford, No. 74 – The third-year offensive lineman has started games at both guard and tackle during his young career.

OT Spencer Brown, No. 79 – Buffalo's third-round pick (93rd overall) in the 2021 NFL Draft spent last season training with former All-Pro tackle Joe Staley.

OG Jon Feliciano, No. 76 – The versatile offensive lineman returns to Buffalo after signing a three-year contract extension in March.

DE Greg Rousseau, No. 50 – Buffalo's first-round pick in 2021 made an early splash, registering two sacks in three preseason games.

DE Jerry Hughes, No. 55 – The longest-tenured Bills player ranks fifth in team history with 51 sacks.

DE A.J. Epenesa, No. 57 – The defensive end progressed steadily as a rookie in 2020, playing at least 34 percent of defensive snaps in each game after the bye.

DT Justin Zimmer, No. 61 – Recorded 21 tackles in 2020, including the game-winning forced fumble against New England in Week 8.

DT Ed Oliver, No. 91 – Registered 34 tackles, three sacks and six tackles for a loss in 2020.

DE Boogie Basham, No. 96 – Selected 61st overall by the Bills in the 2021 NFL Draft, Basham tallied one sack and two tackles for loss during the preseason.

DE Efe Obada, No. 93 – London native became the first player from the NFL International Pathway Program to make a 53-man roster with Carolina in 2018.

DT Vernon Butler, No. 94 – Defensive tackle posted 18 tackles, including five for a loss, and a forced fumble during his first season with the Bills in 2020.

DE Mario Addison, No. 97 – The veteran returns for his second season in Buffalo after leading the team with five sacks in 2020.

Space-eating defensive tackle returns to the Bills after opting out of the 2020 season due to the COVID-19 pandemic.

DT Harrison Phillips, No. 99 – Nominated by teammates for the Walter Payton Man of the Year Award in 2020.

LB Tyler Matakevich, No. 44 – Led the Bills with 10 special teams tackles in 2020.

LB Tremaine Edmunds, No. 49 – The fourth-year linebacker is one of two players in NFL history to record 300-plus career tackles before the age of 23, along with five-time All-Pro Luke Kuechly.

LB A.J. Klein, No. 54 – Registered 4.5 sacks during the month of November last season, which led all NFL linebackers.

LB Andre Smith, No. 59 – Appeared in 12 games with the Bills in 2020, recording seven tackles on defense with one tackle for a loss.

LB Tyrel Dodson, No. 53 – Undrafted linebacker returns for his third season in Buffalo after posting 20 tackles in 10 games in 2020.

LB Matt Milano, No. 58 – The Bills went 10-0 last season in games with Milano, who returns on a four-year extension.

CB Taron Johnson, No. 24 – The nickel corner left his mark on Buffalo's postseason run, intercepting Baltimore QB Lamar Jackson and returning it 101 yards for a game-changing touchdown in the Bills' 17-3 Divisional Round victory.

CB Tre'Davious White, No. 27 – Named Second-Team All-Pro last season and earned his second Pro Bowl selection.

CB Dane Jackson, No. 30 – Started at cornerback and registered an interception in his NFL debut against the Jets last season.

CB Siran Neal, No. 33 – Played 62-percent of special teams snaps in 2020, a career high.

CB Levi Wallace, No. 39 – Undrafted cornerback enters his fourth season with the Bills after ranking second on the team in interceptions (2) and passes defended (9) in 2020.

S Jordan Poyer, No. 21 – Since joining the Bills in 2017, Poyer is the only NFL player with 400-plus tackles, 10-plus interceptions, and five-plus sacks.

S Micah Hyde, No. 23 – The veteran is one of four defensive backs in the NFL with 17-plus interceptions and four-plus sacks since 2013.

S Damar Hamlin, No. 31 – Sixth-round pick led the University of Pittsburgh in tackles (67) and pass breakups (7) last season.

S Jaquan Johnson, No. 46 – Sixth-round pick in 2019 is entering his third season with the Bills.

K Tyler Bass, No. 2 – Returns for his second season after setting a franchise record with 141 points as a rookie in 2020.

P Matt Haack, No. 3 – Joins the Bills after four seasons in Miami, where he stands as the Dolphins' all-time leader in net punting average (39.9).

LS Reid Ferguson, No. 69 – Long snapper signed a three-year contract extension in May.