Statement to support a domicile change. The statement must include detailed information about the domicile change.Most users should use Affidavit of Domicile (MPC 485). If you need to save a partially filled-out form, you may choose to use the alternative form:. If required to file, a copy of the income tax return you filed with any other state. To change domicile, a taxpayer must demonstrate that he has taken affirmative steps consistent with his declaration. Prepare and file a Massachusetts income tax return and mark it as "FINAL RETURN. If you want to sponsor someone for a family-based green card, you need to provide proof of a U.S. domicile in your Affidavit of Support (Form I-864). Simply put, your domicile is your home—the state you consider your permanent place of residence.