Filing Requirements

Who must file an Illinois tax return?

An Illinois resident taxpayer, must file Form IL-1040, Individual Income Tax Return, if

you filed a federal income tax return electronically or by paper; or
you were not required to file a federal income tax return, but your Illinois base income is greater than your Illinois exemption allowance.

An Illinois resident taxpayer who worked in Iowa, Kentucky, Michigan, or Wisconsin, must file Form IL-1040 and include as Illinois income any compensation you received from an employer in these states. Compensation paid to Illinois residents working in these states is taxed by Illinois. Based on reciprocal agreements between Illinois and these states, these states do not tax the compensation of Illinois residents.

If your employer in any of these states withheld that state’s tax from your compensation, you may claim a refund of that state’s tax withheld by filing the correct form with that state. You may not claim tax withheld by an employer in these states as a credit on your Illinois return.

A retired Illinois resident taxpayer who filed a federal return, you must file a Form IL-1040. However, certain types of retirement income ( e.g., pension, Social Security, governmental deferred compensation) are not taxed by Illinois. Read the instructions for “Federally taxed Social Security benefits and certain retirement plans” to see what types of retirement income you may subtract.

A part-year resident taxpayer ( i.e., you were a resident of Illinois for part but not all of the tax year), must file Form IL-1040 and Schedule NR, Nonresident and Part-Year Resident Computation of Illinois Tax, if

you earned income from any source while you were a resident,
you earned income from Illinois sources while you were not a resident, or
you want a refund of any Illinois Income Tax withheld.

For more information, refer to Schedule NR, Nonresident and Part-Year Resident Computation of Illinois Tax, and that schedule’s instructions.

A nonresident taxpayer ( i.e., you were not an Illinois resident at any time during the tax year), must file Form IL-1040 and Schedule NR if

you earned enough taxable income from Illinois sources to have a tax liability (i.e., your Illinois base income from Schedule NR is greater than your Illinois exemption allowance on Schedule NR), or
you want a refund of any Illinois Income Tax withheld in error. You must attach a letter of explanation from your employer.

For more information, refer to Schedule NR, Nonresident and Part-Year Resident Computation of Illinois Tax, and that schedule’s instructions.

An Iowa, Kentucky, Michigan, or Wisconsin resident who worked in Illinois, must file Form IL-1040 and Schedule NR if

you received income in Illinois from sources other than wages, salaries, tips, and commissions (you must pay tax on this income regardless of residency);or
you want a refund of any Illinois Income Tax withheld.

If you received compensation from Illinois employers, you are not required to pay Illinois Income Tax on this income. This is based on reciprocal agreements between Illinois and these states and applies only to compensation you received from wages, salaries, tips, and commissions. The reciprocal agreements do not apply to any other income you might have received, such as Illinois lottery winnings.

An Illinois resident who was claimed as a dependent on your parents’ or another person’s return, might not be exempt from tax. You must file Form IL-1040 if

your Illinois base income is greater than $2,000, or
you want a refund of Illinois Income Tax withheld from your pay.

Note: If your parent claimed your interest and dividend income through U.S. Form 8814, do not count that income in determining if you must file your own Form IL-1040.

The surviving spouse or representative of a deceased taxpayer who was required to file in Illinois, you must file any return required of that taxpayer. Please refer to the special instructions on how to file for a deceased taxpayer.

A student, is not exempt from tax nor are there special residency provisions for you. However, income, such as certain scholarships or fellowships, that is not taxable under federal income tax law, is also not taxed by Illinois.

A nonresident alien taxpayer, is not exempt from tax. If your income is taxed under federal income tax law, it is taxed by Illinois. You must attach a completed copy of your U.S. 1040NR or U.S. 1040NR-EZ.

Even if you are not required to file Form IL-1040, you must file to get a refund of any Illinois Income Tax withheld from your pay or any estimated tax payments you made.

What if I live in Illinois but have income in another state?

As an Illinois resident you are subject to tax on all income no matter where it is earned. You will need to contact the other state for any filing requirements. If you are required to file and pay tax on that income you may be allowed a credit with Illinois on Schedule CR, Credit for Tax Paid to Other States.

I live in another state but worked in Illinois. What state do I file with?

You will need to contact your home state for its filing requirements. As a nonresident you are required to file the IL-1040 and Schedule NR and pay tax on income earned from an Illinois source, unless you live in Iowa, Kentucky, Michigan or Wisconsin. Residents of those states are not taxed by Illinois on their wages or salaries from jobs in Illinois, and no Illinois income tax withholding is required. If your employer is withholding Illinois tax, you should fill out a Form IL-W-5-NR, Employee's Statement of Nonresidence in Illinois, and give it to your employer so they will stop the withholding, and you will need to file an Illinois return to get any withholding refunded to you. You are also required to file and pay tax on any income you earned from Illinois sources other than your wages or salary.

When is my tax return due?

Your Illinois filing period is the same as your federal filing period. We will assume that you are filing your Form IL-1040 for the calendar year unless you indicate a different filing period in the space provided at the top of the return. The due date for 2007 calendar year filers is April 15, 2008. You are granted an automatic six-month extension in which to file your Form IL-1040, Individual Income Tax Return. An extension of time to file is not an extension of time for payment of Illinois income tax. You must use Form IL-505-I, Automatic Extension Payment for Individuals, to pay any tax you owe in order to avoid penalty and interest on tax not paid by April 15, 2008. If you do not expect to owe tax, you do not have to do anything.

Where do I mail my return?

Refund
If you are sending your return without a payment, mail your return to:

ILLINOIS DEPARTMENT OF REVENUE
SPRINGFIELD IL 62719-0001

Balance Due
If you are sending a payment with your return, mail your return to:

ILLINOIS DEPARTMENT OF REVENUE
SPRINGFIELD IL 62726-0001

How do I determine my filing status?

You should select the filing status that you checked on your federal return unless you filed a joint federal return and are filing separate Illinois returns due to residency issues. If you did not file a federal return, check the filing status that you would have checked if you had filed one.

If you are filing a joint return and one spouse is a full-year Illinois resident while the other is a part-year resident or a nonresident, you may choose to file "married filing separatelyfor Illinois." (example: military personnel) In this case, each spouse must determine the income and exemptions as if he or she had filed separate federal returns. You may not subtract your spouses' out-of-state income on your IL-1040.

If you choose to file a joint return, you must treat both spouses as residents. This election is irrevocable for the tax year. Because both of you will be treated as full-residents and all income will be allocated to Illinois. You may be allowed a credit for income tax paid to another state.

What are estimated payments and how do I make them?

You must make estimated income tax payments if you can reasonably expect your 2008 tax liability to exceed $500.00 after subtracting your withholding, credits for Illinois Property Tax paid, income tax paid to other states, Education Expense credit, and tax credits from Schedule 1299-C. You are likely to meet this requirement if your income is either fully or partially exempt from Illinois withholding. If you plan to file a joint income tax return, you must figure your estimated tax on the basis of your joint income. For more information, refer to the IL-1040-ES, Estimated Income Tax Payments for Individuals.