For Utah tax purposes, a person is considered domiciled in Utah under certain conditions. Your domicile is the location of your permanent home.A resident is a person who is domiciled in Utah for any period during the tax year, but only for the duration of that period. "Nonresident" Defined. Before you can turn in your Utah residency form, you must live in Utah for 12 or more continuous months. An affidavit of domicile is a legal document that verifies the primary place of residency of someone after their death. If you have spent 180 days or more of a calendar year in Utah, Utah considers you a resident for tax purposes. Domicile refers to the place you call home permanently. Your domicile is important for legal purposes such as paying taxes, voting, and claiming benefits.