Married. You are considered married for the whole year if you were married as of December 31 OR If your spouse died during the year, consider yourself married for the whole year. A marriage means only a legal union between 2 people. You are considered married if:- You are separated, but you haven't obtained a final decree of divorce or separate maintenance by December 31.- You are separated under an interlocutory decree. This isn't a final decree. If you are married, you and your spouse may be able to file a joint return or you may file separate returns. A married person who qualifies to use the head of house-hold filing status for federal tax purposes may also use the head of household filing status for Wisconsin. The marital property law has little effect on the filing of joint returns. Your tax will generally be lower if you file a joint return. However, you should figure your tax on both a joint return and separate returns to make sure you and your spouse are using the method that will result in the lowest tax.
Divorced taxpayers. You are still jointly and individually responsible for any tax, interest, penalties, and fees due on a joint return filed before your divorce. However, this responsibility does not apply if:- A judgment of divorce entered on or after June 21, 1996, apportions that liability to your former spouse, and- You provide the department with a copy of that portion of the judgment of divorce that relates to the apportionment of tax liability.