Complete Lines 1 through 10 of your Form IL-1040 as if you were a full-year Illinois resident. Follow the Form IL-1040 Instructions.Your domicile is the place where you reside and the place where you intend to return after temporary absences. I work seasonally in multiple states and use my parents address in IL for license, documents, etc. Domicile is intended to be permanent rather than temporary, whereas residence means living in a particular locality and requires mere physical presence. Some states classify you as a full-year resident if you lived there for at least 183 days, although others have different thresholds. Use our Affidavit of Domicile form to verify the last home address of a deceased person to speed up the inheritance process. It is not unusual for people to relocate from Illinois to states with warmer climates and lower income taxes, such as Florida, Tennessee, Texas, and others.