A declaration is a simple statement that you intend in good faith to return to the United States to resume your domicile. Complete Form ET-141 if it is claimed that the decedent was not domiciled in New York State at the time of death.Providing proof of domicile in the United States is critical for most people when submitting Form I864, Affidavit of Support. The following list contains some of the factors courts have considered as indicative of an intent to establish domicile in a new state. I'm a US citizen (USC) residing in Canada with my wife who is the principal applicant. A Declaration of Domicile proves residency in Broward County, Florida. It is often used to enroll children or college students in school. Do I need to file a New York State tax return? How do I know if I am a resident of New York State for income tax purposes? It is presumed that the domiciles of a husband and wife or civil union partners are the same, unless there is affirmative evidence to the contrary.