Selena Gomez Celebrates 33rd Birthday with Benny Blanco and Taylor Swift!

Selena Gomez celebrated her 33rd birthday with her fiancé, Benny Blanco, and some close friends -- and she had a very special guest, too.

Taylor Swift showed up to her BFF's bday bash Sunday with a 1970s "Saturday Night Fever" theme -- and everyone had one helluva great time!

Check out photos posted to Selena's Instagram page ... In one, Taylor and Selena pose together surrounded by balloons. Taylor wears a glittering dress, and Selena sports a shiny jumpsuit.

Other pics capture Selena -- also wearing a white fur coat -- hanging out with her other friends, including actress Sofia Carson, and, of course, Benny.

Selena is even snapped planting a big fat kiss on Benny's lips. By the way, Benny got into the whole party theme with his 70s style get-up.

As you know, Selena and Benny are planning to tie the knot after Selena announced their engagement in a December 2024 IG post with a picture of a huge rock on her finger. The couple started dating back in July 2023, and they've been inseparable ever since.