The Buffalo Bills' biggest and most notable rivals are the Miami Dolphins and the New England Patriots. The Dolphins and the Bills have a long history marked by competitive regular season and playoff matchups, with Miami historically dominating in the 1970s but Buffalo gaining an edge in the 1990s and still holding a playoff advantage. The rivalry is fueled by regional and stylistic contrasts between the two cities. The New England Patriots became a main rival during the Tom Brady era when they dominated the AFC East for two decades, though Buffalo has gained ground since Brady's departure. Other significant rivals include the New York Jets, Kansas City Chiefs, Cleveland Browns, and Tennessee Titans (formerly Houston Oilers), with the Chiefs also being a frequent playoff adversary in recent years. Summary of key Bills rivals:

• Miami Dolphins: Long-standing rivalry with multiple playoff meetings; Bills lead in playoffs but Dolphins have a slight overall edge.
• New England Patriots: Intense rivalry especially during the Tom Brady years; Bills have had recent success post-Brady.
• New York Jets: Divisional rival with less intensity but still competitive.
• Kansas City Chiefs: A strong playoff rivalry in recent years, often affecting postseason outcomes.
• Cleveland Browns and Tennessee Titans: Notable but less intense rivalries for the Bills.

These rivalries shape much of the Bills' competitive and fan culture history.