Sweater weather is a state of mind.

Taylor Swift returned to one of her longtime favorite labels to catch Cara Delevingne’s penultimate performance in “Cabaret” in London last Friday, wearing a sky blue Stella McCartney sweater ($1,690) with a fringed hem.

Trading her bedazzled Eras Tour costumes for something cozier, the Grammy winner pulled her pal in for a hug backstage after the show, as seen in a snap Delevingne shared on Instagram Thursday spotlighting some special moments from her several-month-long run as Sally Bowles.

It makes perfect sense that Swift would opt for Stella for this particular outing; the vegan brand’s been a go-to of hers since her 2019, when the pair collaborated on a collection inspired by Swift’s “Lover” album. (One of the tracks, “London Boy,” even includes a shout-out to the British designer.)

In addition to incorporating McCartney’s sustainable styles into many of her street style looks since then, the “Cruel Summer” singer also posed in one of Stella’s plaid coats for the cover of her woodsy “Evermore” album in 2020.

“Stella is so creative,” Swift told fans during a YouTube Q&A ahead of her music video premiere for “Willow,” the album’s lead single.

“I told her I had a secret project and she designed clothes that were EXACTLY what I imagined. I drove to her office, picked them up and took them into the woods!!”

Clearly, the appreciation is mutual; “Knowing someone well makes creating something for them easier. With Taylor, everything happened so naturally; the pieces I made reflected the effortless emotionality of her album,” McCartney wrote on Instagram at the time.

“Complementing a friend’s creation is rare and precious and feels incredibly special.”

Delevingne’s long been close with McCartney as well, having walked in her runway shows, attended multiple Met Galas in her designs and, most recently, starred as the face of her brand’s summer 2024 campaign.