The Chiefs-Bills game shattered records with an audience of 57.4 million, topping last year’s AFC Championship and surpassing the 2012 Giants-49ers game. However, Sunday night’s early game saw a significant drop in viewers compared to last year’s Commanders-Eagles game (44.2 million vs. 55.4 million). When combining both games this season, the average audience was 50.8 million, down from last year’s 56 million.
Source: https://www.nbcsports.com/nfl/profootballtalk/rumor-mill/news/chiefs-bills-game-soars-to-afc-championship-record-audience