Kate Bosworth Flashes Diamond Ring as She Makes Red Carpet Debut With Justin Long

The pair first sparked dating rumors in 2020.

Kate Bosworth and Justin Long made their red carpet debut as a couple on Sunday at the Vanity Fair Oscars after-party -- but that's not what made onlookers turn their heads.

Bosworth and Long made their arrival in coordinating black tie looks, with Long keeping things traditional in a black tux, while his lady wore a flowing black-and-cream gown. However, Bosworth had another accessory, a diamond ring on that finger.

While posing with her love, Bosworth showed of the diamond rock, which was the only piece of jewelry on her hands. At no time did she or Long mention an engagement.

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John Shearer/WireImage
John Shearer/WireImage

ET has reached out to Bosworth's rep regarding the engagement speculation.

Long, 44, and Bosworth's outing comes after the Barbarian actor penned a sweet message to Bosworth in honor of her 40th birthday in January.

In the post, Long gave a shout-out to the Blue Crush actress, saying, "She is also the best part of my day, everyday - even when we’re not together."

"She’s fiercely committed to the truth. She’s so fun to work with. She’s the most fun to do everything with. She is genuinely curious about people and the world. She makes everything in my life better - all my favorite songs and movies, vacations and sunsets and Chinese food," Long continued.

"She strives to be better but she’s the best person I know. She will do anything for her friends. She is so generous she makes my parents slightly uncomfortable around the holidays (she also makes the best cookies). She is the most beautiful human being I’ve ever seen. She is purely good. She will stand up to anyone who isn’t. She has true integrity and grit. She has, by far, my favorite smile," he added.

Bosworth and Long have been rumored to be dating since 2020. The couple went public with their romance in April 2022, before making their love Instagram official last May.