| Your son would have a fairly complicated tax situation requiring him to file multi-state individual tax returns and should definitely seek a tax professional to file his 2009 tax return. The reason is the following;
1. Wisconsin State Income Tax Return
Since your son was a part year resident of Wisconsin may be required to file a Part-Year resident Wisconsin State individual income tax return for the period of his residency.
Wisconsin Income Tax Law states that "If you are a nonresident or part-year resident of Wisconsin and your Wisconsin gross income (or the combined gross income of you and your spouse) is $2,000 or more, you must file a Wisconsin 1NPR. Even if you do not have to file, if you had Wisconsin income tax withheld from your wages or you paid estimated tax, you should file a Wisconsin return since this is the only way to get a refund."
It is also worth remembering, that "during the time you are a Wisconsin resident, Wisconsin taxes your income from all sources. During the time you are not a resident of Wisconsin, Wisconsin only taxes your income from Wisconsin sources."
2. Maine State Income Tax Return
Since he worked in Maine State, he would have been subject to the Maine Withholding Tax and may be required to file a Maine State Tax Return for the W-2 that has income attributable to Maine State.
Maine State Income Tax Law states that "If you are a nonresident for all or part of the year and your Maine gross income meets the Maine minimum filing requirement, you must file Form 1040ME and include Schedule NR, Nonresidents/Part-Year Residents, or Schedule NRH, Nonresident.'
Additionally, the Maine State Income Tax Law also states that "Part-year residents, nonresidents and "safe harbor" residents must file a Maine return based on their total federal adjusted gross income. Your tax liability is first calculated as if you were a resident of Maine for the entire year. You are then allowed to calculate a nonresident credit on Maine Schedule NR that will reduce your Maine tax by the portion of the tax that is related to the income you earned outside the state while a nonresident or "safe harbor" resident of Maine."
3. New York State Income Tax Return
Since your son was a part year resident of New York State may be required to file a part year resident New York State tax return for the period of his residency. Of course he would be entitled to any allowable deductions and exemptions related to his New York Individual State Income Tax applicable to Part Year Residents.
New York State Income Tax Law states that "If you were a resident of New York State for only part of 2009, you are subject to New York State tax on all income you received while you were a resident of the state and on income you received from New York State sources while you were a nonresident." So, it is possible that your son had some income whilst a resident in New York and hence would be required to file "Form IT‑203, Nonresident and Part-Year Resident Income Tax Return."
It is for this reason that I strongly suggest that you consult a Tax Professional who is experienced in Multi-State Tax filing to assist you in perparing your son's 2009 tax return.
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