State

Illinois income tax is based, to a large extent, on the Federal Internal Revenue Code (IRC).

State income taxes are generally based on your Form IL-W-4 number of allowances claimed. Income taxes are withheld from pay using the State of Illinois income tax rate of 4.95%. Illinois State University utilizes the automated payroll method for computing State of Illinois income taxes.

• Taxable Gross Explanation
• State Income Tax Calculation
• State Income Tax Table
• Illinois Booklet 700-T

Reciprocal States

Illinois has income tax reciprocity agreements with four states; Iowa, Kentucky, Michigan, and Wisconsin. If you are a resident of Iowa, Kentucky, Michigan, or Wisconsin, and you do not want Illinois income taxes withheld from the wages you earn for work at Illinois State University, you must complete Form IL-W-5-NR, Employee's Statement of Nonresidence in Illinois. If you change your state of residence, you must notify your employer within ten days.