According to People, a source close to Taylor told the magazine that the two are "very happy together."
"Her decision to keep her relationship with Joe quiet is making her happy," the source said. "They have been getting to know each other slowly without any pressure."
Joe and Taylor have spent the last few months flying back and forth between the U.S. and Joe's native U.K., where he was filming his next movie, The Favourite.
Joe apparently, "is very happy about spending time at home with Taylor," and "they seem to be on the same page. Joe is getting to know Taylor’s parents and everyone likes him. He is very supportive of her work."
Taylor and Joe were first linked to one another in June last year, and it has been her most secretive relationship yet.
"It was her goal to keep it a secret even though it's all really light still. She barely told any of her friends. She got buried in media being on top of her life during the last relationship, so she tried everything in her power to not have that happen again. She worked very closely with her security team and management to make sure her life going forward was private. All of that madness really affected her."