IMPORTANT — Read Instructions before completing this form. California Affidavit of Domicile Form.How do I fill this out? If you use Form 540NR, figure your taxable income as if you were a California resident for the entire year. Under California law, a homeowner is entitled to the protection of a certain amount of equity in the home that is his or her principal residence (home). ATTENTION: Only use this form if the decedent was domiciled in the 50 U.S. states or the District of Columbia at the time. The property must be your principal place of residence and you can only have one declaration at a time. California Affidavit of Residence Form. Use our Affidavit of Residency form to verify your home address for official purposes.