Records are meant to be broken, and several were in Week 18 of the 2021 season. Below is a list of new marks that were set in the final week of the regular season.
- Baltimore Ravens tight end Mark Andrews surpassed Derrick Mason for the franchise's single-season receptions record (103).
- Cincinnati Bengals rookie wideout Ja'Marr Chase broke Chad Johnson's franchise mark for receiving yards in a single season (1,440).
- Dallas Cowboys quarterback Dak Prescott tossed five touchdowns in a win over the Eagles to finish with 37 for the season, eclipsing Tony Romo's team record.
- Detroit Lions wideout Amon-Ra St. Brown passed Roy Williams' franchise record for receiving yards by a rookie (817).
- Green Bay Packers wideout Davante Adams set the franchise record for receiving yards in a single season, breaking Jordy Nelson's mark from 2014 (1,519).
- Miami Dolphins wideout Jaylen Waddle broke Anquan Boldin's single-season record for receptions by a rookie (101).
- Pittsburgh Steelers linebacker T.J. Watt tied Michael Strahan's NFL record for sacks in a single season (22.5).
- Tampa Bay Buccaneers quarterback Tom Brady broke Drew Brees' NFL record for completions in a season (471). Brady also became the oldest player (age 44) in NFL history to pass for 5,000 yards in a season. Wideout Mike Evans caught his 14th touchdown of the season, setting the franchise record. He also reached the 1,000-yard receiving mark for the eighth consecutive season, extending his record for the most consecutive 1,000-yard receiving seasons to begin a career in NFL history.