Jerz wrote:
It's up to you whether to change your state of residence, I think IL allows you to keep your legal residence in another state if you live in IL as a student. With regard to taxing out of state earnings, in the NYC region (where a lot of people work across state borders from where they live) the states have reciprocal agreements where, if you're a resident of state A and work in state B, state B applies their tax rate to income earned in their state, plus state A applies their tax rate to income earned in state B but then gives you a credit for taxes paid to state B. The net impact being if your home state has a higher tax rate than the state in which you work, your state will charge you the difference. I'm not familiar enough with Illinois tax law to know if they charge income tax on out-of-state earnings, but it wouldn't surprise me if they did.
One other point to make: a flat tax state like IL may make you worse off as a student with low income than a state with a progressive income tax system. So for example, if I became a IL resident and make $30,000 during my 3 month internship next year, I'd pay tax at 3% on that income. However, if I stay a NJ resident (where there's a progressive system), I'd only be taxed at 1.7%.
Interesting. I need to figure out if I can keep Texas as my state of residence while I'm in school since we have no state income tax. Although, I'll technically be packing up everything and leaving hen I move for school. i.e. I'll have no legal ties when I leave, expect my driver's license and voter registration.