Once you are married with your prospective spouse, you need to lodge an application for a Partner visa (Subclasses 820 and 801) before your Prospective Marriage visa (Subclass 300) ends.
What do I do after I get married?
A Notice of Intended Marriage must be completed and lodged with the marriage celebrant at least one calendar month before a marriage ceremony can be solemnised. This is an important document that must be included in your application as a proof that you plan to marry your prospective spouse.
What is Notice of Intended Marriage Form and do I need it for the application?