Pair have been dating since the summer
The pair are said to have hooked up over the summer.
Kaya, 17, who plays Effy Stonem, and Elliott, 20, even enjoyed a romantic holiday in Barbados at Christmas.
Elliott is the twin brother of Emmerdale star Luke Tittensor.
Kaya was previously linked to Jack O’Connell, 20, her co-star in the E4 drama.