The pair have purchased a "very private" three-bedroom Beverly Hills home, a real estate insider confirms to PEOPLE.
The traditional house comes complete with a pool, lush garden and nearby private hiking trails, which caught Kutcher's eye immediately.
"Ashton and Mila both love the house, and they think it's perfect for raising a family. They plan on moving in before the baby is born," says the insider.
"They are looking for more security now that they have a baby on the way. They're in the nesting phase," says a second source close to Kutcher.
Now, on to babyproofing!
Reporting by PERNILLA CEDENHEIM