Your state of residence would be your resident state as of December 31, 2018. But be sure to indicate in the My Info section that you lived in another state during the year, and identify the other state as Wisconsin.
If your new state has an income tax, you'll be filing a part-year resident in both it and Wisconsin. If it doesn't, you'll be filing a part-year resident return only in WI.
I moved to Indiana for schooling purpose, as I started Graduate school at Butler University. I did not work since I moved (only school/education), so from August 11 - December 31 2018. I have not changed my identification address, is because I wasn't sure the place I was living at was my choice of home.
If your main home is still in Wisconsin, and you only went to Indiana temporarily for school purposes, then your state of residence for tax purposes would remain Wisconsin.
Your state of residence would be your resident state as of December 31, 2018. But be sure to indicate in the My Info section that you lived in another state during the year, and identify the other state as Wisconsin.
If your new state has an income tax, you'll be filing a part-year resident in both it and Wisconsin. If it doesn't, you'll be filing a part-year resident return only in WI.