I am getting married in June and my fiancé and I want to know how long we have to be married for before he can adopt my son. My son's bio father is in agreement with the adoption, just wanted to know if we could start the process the day after we are married or if a time has to pass before he can adopt him.

ANY question on law needs to include your general locale as laws vary by area.

But since you really should have an attorney prepare the petition for you, you can start shopping for an attorney now. Once you decide on an attorney they will guide you as to how long the process will take.

Since you are going to need an attorney go see one, while most places are a year, other issues as to how long you have been together and other factors can have some input.