Debuts On Brittany Mahomes Instagram

Taylor Swift Brittany Mahomes

Taylor Swift and Brittany Mahomes' friendship is Instagram official ... 'cause the wife of the Chiefs superstar QB finally shared a personal pic from their weekend in NYC where the singer spent some quality time with a few fellow K.C. WAGS!

Of course, Patrick's partner hit the Big Apple with Swift and her VIP gal pals Selena Gomez,Sophie Turner and Gigi Hadid a few days back ... locking arms with Travis Kelce's new boo outside the Bond Street restaurant.

Taylor Swift Brittany Mahomes

Judging by Brittany's new social media posts, it looks like Taylor made some time for her new friends on Saturday, too -- Chiefs backup quarterback Shane Buechele's wife, Paige, and…