The actress, who made it big thanks to her role in Skins, has been dating fellow actor Benjamin Walker for just a couple of months.
But it seems the pair are already planning their lives together as Kaya took to Instagram to share snaps of her, her new ring and her man.
On Sunday (28 December) Kaya cooed: "@findthewalker thank you for making me the happiest woman in the world."
The caption accompanied a picture of the two sharing a major kiss. Cute!
Kaya, who's been filming the sequel to film Maze Runner in New Mexico, also posted a snap of the happy couple with her mum and the whopping ring on her engagement finger is clear to see.
It appears that Kaya has now made the move across the pond to live with her 32-year-old American beau, as she added: "Showing mum around our new home."
The star, 22, used to live in London and recently admitted: "Ben lives in New York and I live in London, so we have to work hard to see each other. You have to go for it, which I like."
But now that they've moved in together, are looking seriously loved up and are planning a wedding, we think this pair are in for a pretty sweet 2015.
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