Taylor Swift has proven again that she's one of Selena Gomez's biggest fans.

The "Blank Space" singer expressed her support for her longtime BFF over the release of her new song "Single Soon" on her Instagram Stories Aug. 26.

"When ur bestie is the bestest," Taylor wrote, under the single's music video.

The pop star, who earlier this year went through a breakup with actor Joe Alwyn following a six-year relationship, and months later, ended a whirlwind romance with 1975 singer Matty Healy, added, "Will be dancing to this forever methinks."

On Aug. 26, Selena reposted Taylor's post on her own Instagram Stories.

She also recently thanked her fans for their support over the song's release. "Thank you guys for all the love on Single Soon!!!" she wrote on her Instagram. "It's a playful anthem about being comfortable in your own skin and loving your own company… and it's also really fun to dance to!"

"Single Soon" was released Aug. 25. The track begins with a voicemail from Selena's sister Gracie Teefey.

"Hi!" the 10-year-old says. "I love you, sissy. Never worry about boyfriends at all."

Selena has been friends with Taylor for more than a decade and last month attended one of her bestie's Eras tour concerts in Los Angeles with Gracie.

In July, the Only Murders in the Building actress and other several members of Taylor's famous "squad" attended the singer's Fourth of July party. Other guests included members of the band HAIM, who wrote on Instagram following the bash, "Single summer."

Meanwhile, Selena posted at the time, "Sometimes you need to be around empowering, kind and kick ass gals. I needed that."

Look back at Selena and Taylor's cutest BFF pics over the years below:

The two celebrate Independence Day together with friends at Taylor's party.

The two pose for a pic at Taylor's 2023 party.

Selena celebrates her 30th birthday with friends, including Taylor, 32.

Selena writes on her Instagram, "30, nerdy and worthy."

"I'm grateful for those I surround myself with. And this woman right here happens to be one of my favorites. Love our tradition and I love you," wrote the "Hands to Myself" singer in a sweet Instagram pic posted the day after their reputation show.

Reuniting onstage for the "Look What You Made Me Do" singer's Rose Bowl concert, the longtime besties serenade the crowd with Gomez's hit "Hands to Myself."

The two share a sweet moment onstage at Taylor's reputation tour concert at the Rose Bowl in Pasadena, Calif. in May 2018.

The two arrive at the 2016 Grammy Awards.

The two hug at the 2016 Grammy Awards.

During the 2016 iHeartRadio Music Awards, the iconic pair pose with "Starlight" singer Serayah.

The two embrace during the 2016 iHeartRadio Music Awards.

The "Bad Liar" singer gives her bestie a tight hug backstage of the 2016 iHeartRadio Music Awards. That night, Swift won four awards—Female Artist, Tour, Meme-able Moment and Album—and Gomez won TripleThreat.

The two perform onstage during Swift's 1989 tour show in Los Angeles on Aug. 26, 2015.

The two appear at the 2015 MTV VMAs.

"Happy birthday my nugget. #girlsnighttothefullest," writes the "Wolves" singer on Instagram for Cabello's special day.

In celebration of Camila Cabello's 18th birthday in 2015, the "Havana" singer surrounds herself with famous friends, including the "Delicate" pop star, the "Back to You" singer, Jaime King, Hailee Steinfeld, Sarah Hyland, Joey King, Hayley Williams and the Haim sisters.

The two hang out at the 2014 American Music Awards.

They know they both got it.

The two hang out at the 2014 Met Gala, as seen in this Instagram video.

The besties join Nicki Minaj and Katy Perry at the 2011 American Music Awards.

Are they out of the woods yet? In a funny Instagram post, the besties pose in major greenery and joke about Swift's 2016 hit.

At the 2011 American Music Awards, the star besties have some fun and make their 3-D glasses and neon sticks look glamorous.

The two hang out at the 2011 American Music Awards.

The two look adorable at the premiere of Another Cinderella Story in 2008.