It’s official: Taylor Swift is … BFFs with Brittany Mahomes.

Swift, the 12-time Grammy Award winner, is attending Sunday’s Chiefs-Chargers game at Arrowhead Stadium.

It’s her fourth Chiefs game of the season as her reported romance with Kanas City tight end Travis Kelce blossoms.

Swift is sharing a suite Sunday with Brittany Mahomes, the wife of Chiefs quarterback Patrick Mahomes.

Early in the second quarter, after Marquez Valdes-Scantling’s 46-yard touchdown reception, CBS showed footage of Swift and Mahomes celebrating, slapping hands five times to start their handshake.

Swift has had much to celebrate Sunday.

Kelce had nine receptions for 143 yards and one touchdown in the first half as the Chiefs built a 24-17 lead.

Earlier, Swift, 33, was seen in a red Chiefs top, black skirt, and matching boots as she arrived at the stadium for the game.

Most recently, Swift attended the Chiefs’ 19-8 victory over the Denver Broncos on Oct. 12, where she shared a suite with Kelce’s parents, Ed and Donna Kelce, along with Brittany Mahomes.

After the “Thursday Night Football” game, Kelce and Swift took advantage of the free weekend with a trip to New York, where they were photographed holding hands days after the game.

The duo stopped by the “Saturday Night Live” afterparty last weekend, shortly after making surprise appearances on the Season 49 premiere.

Kelce appeared in a football skit about him and his new beau taking over the NFL broadcasts, while Swift made a cameo to introduce her friend Ice Spice for one of her musical performances of the night.

The following day Kelce was photographed leaving the “Cruel Summer” singer’s NYC apartment.

The couple also spent part of their Sunday taking in a meal at the Waverly Inn.