The singer-and-actress and the American hunk - who have been dating since they met on the set of their TV movie 'Northern Lights' last year when they were both married to other people - have decided to commit to one another, with Eddie and his two young sons moving into LeAnn's home.
LeAnn's representative confirmed the news to People.com, saying: "They're excited for this happy new journey."
Eddie and LeAnn decided to live together at the lavish house in Los Angeles' San Fernando Valley, after the actor's lease ran out on his home.
They now plan to move into their new family home with Mason, seven, and three-year-old Jake - who he shares joint custody with his ex, Brandi Glandville - over the next few weeks.
A source said: "It just made sense for them. Eddie's lease was up and LeAnn's home was bigger and already familiar to Eddie's sons.
"It's somewhere the kids know and it allows Mason to stay in the same school district, which was important to them, that there's continuity for him. They take moving in with the kids with a lot of responsibility. They want to make sure that it was done in the right way."
LeAnn finalised her divorce from her ex-husband Dean Sheremet last month, after the actress embarked on an affair with Eddie in early 2009.