Medicare should be notified of the billing service change using the appropriate CMS form. Medicaid depends on the state you are in. The provider's address is not actually changing correct? Just who is doing the billing. You will need to do EDI paperwork to get set up to submit thru whatever clearinghouse you will be using as well. You will need the providers legal business name, EIN/Tax ID, Group and/or individual NPI, PTAN and another other legacy numbers, and address(es). Also name(s) of rendering providers in group.