The NFL is pulling out all the stops for Christmas ... 'cause not only is Beyoncé a halftime performer -- Mariah Carey is kicking off the whole day of games!!
The big announcement was made on Thursday ... with the Queen of Christmas slated to give a special rendition of her classic hit ahead of all the holiday football action.
Carey will perform "All I Want For Christmas Is You" before the Kansas City Chiefs take on the Pittsburgh Steelers at 1 PM ET and the Baltimore Ravens visit the Houston Texans later in the afternoon.