Preheat the oven to 350F.
Mix cream cheese, mayonnaise, sour cream, cheeses, garlic, basil, garlic powder, salt, and pepper together in a medium bowl.
Gently stir in artichoke hearts and spinach.
Transfer the mixture to the prepared baking dish.
Bake in the preheated oven until bubbly and lightly browned, about 25 minutes.
