Sheeran let the news slip at a London event last week.
“I’m not sure that it’s public knowledge, so maybe I shouldn’t have said anything -- but, yes, they’re already living together," the ginger-haired singer told the Mirror.
“Things are moving fast. He moved in and, judging by the last time I saw them, they couldn’t be happier," he added. "They get on really well and are genuinely good friends, pardon the pun.”
Cox broke up with David Arquette last year. They have a 9-year-old daughter together, Coco.
Cox told Wendy Williams in February that she and McDaid had "gone out to dinner a few times."
"My whole thing is that, he's a great man and to have someone kind, that you trust around your kid is the most important part," the Cougar Town star said.
So what about wedding bells?
“I wouldn’t be surprised, but it’s still early days," Sheeran, 23, said. “They certainly enjoy each other’s company and feel very comfortable with each other.”
[Mirror, US Weekly]