Taylor Swift is showing her love for her BFF Selena Gomez, who just released her first single in nearly a year.

"Single Soon," a sultry, upbeat dance track, dropped on Friday, and Gomez wasn't only feeling the support from her fans after the release - her best friend joined in, too.

"When your bestie is the bestest," Swift, 33, wrote on her Instagram Story Saturday as she reshared a reel originally posted by Gomez, 31, featuring several clips from the song's music video.

"Will be dancing to this forever methinks," Swift added of the Benny Blanco- and Cashmere Cat-produced track.

Gomez reposted the "Anti-Hero" singer's post on her own Instagram Story on Sunday.

"Single Soon" is "a playful anthem about being comfortable in your own skin and loving your own company," Gomez wrote on Instagram, adding that "it's also really fun to dance to!"

The song also serves as a teaser for the Only Murders in the Building star's upcoming album, tentatively titled SG3, which she has been working on for much of the last year.

She shared on Instagram that she's "not quite done" with the record, but she wanted to put out the "fun little song" that she said is "perfect for the end of summer."

The Rare Beauty founder even brought her younger sister, 10-year-old Gracie Teefey, in on the fun as she recorded the single. 

"Hi. Love you, sissy. Never worry about boyfriends. At all," Teefey said in the opening scene of the song's music video, which Gomez shared a clip of on Instagram.

Swift and Gomez's friendship is a longstanding one - and a fan-favorite. Though both stars are notoriously private about their lives, they have had quite a few public appearances together so far this year.

In April, Gomez and her sister supported Swift at one of her Eras Tour shows in Arlington, Texas, during which the pop star gifted Gracie her hat in the middle of her Red smash hit "22," a tradition of the tour.

The pair also celebrated July 4th together, and nearly broke the internet as they shared a series of photos from their star-studded holiday celebration.

Swift and Gomez were joined by the musical Haim sisters, Este, Danielle and Alana, as well as stylist Ashley Aivgnone and model Sydney Ness, who was rumored to be dating Swift's brother, Austin, last year.

The photos featured the group of girls posing in swimsuits, as well as a series of polaroid photos that had been taken over the course of the trip. In one shot, Swift posed with her arms wrapped around Gomez's shoulders as the camera captured the duo mid-laugh. 

Earlier this month, Gomez brought her sister to see Swift's Eras Tour once again as the "Lavender Haze" performed for five sold-out shows at Los Angeles' SoFi Stadium to wrap up the tour's U.S. leg. She kept herself low-key in the VIP tent at the concert, but shared a photo of the several dozen friendship bracelets she acquired from fans while there.

"Thank you to the fans who traded with me," she captioned the photo of her impressive collection.