In fact, she's seems to have just confirmed it!
Model Gigi, 20, shared an intimate snap of Zayn, 22, on Saturday (2 January) which had some of her 11.1million Instagram followers talking...
Although the photo doesn't show Zayn's face, his shirtless tattooed torso is unmistakable. And - cuteness overload - he's cuddling a kitten!
A fan remarked: "I can recognise his tattoos ANYWHERE."
Another said: "Thanks for giving me a new shitless picture of Zayn."
Gigi Hadid (@GiGiHadid) December 31, 2015
Just days before, on New Year's Eve, Gigi teased her fans once again by sharing a selfie wearing an out-of-date Bradford City AFC football shirt - Zayn's favourite team.
Clearly chuffed to see the Victoria Secret's model in one of their shirts, the football club responded with the message: "@GiGiHadid @bellahadid Gigi, do you not have the new #bcafc shirt? We'll have to get you one!"
But it was Zayn who responded: "It's a lil old ;)."
Zayn shared their first selfie together two weeks ago, seeming to make their relationship official.
He and Gigi were first linked in November, just weeks after she split up from Joe Jonas, and were soon spotted holding hands in LA.
In now deleted tweets, Gigi defended their relationship against criticism from a fan.
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