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Income Tax

Each employee must complete a Form W-4 when beginning work at ISU. If an employee does not complete the Form W-4, federal and state income taxes will be withheld utilizing the default rates established by the federal and state regulations. The federal default rate is the status of a single filer with no adjustments. The State of Illinois default rate is withholding with no allowances.

Printable W-4 Instructions

ISU will not refund any taxes that were withheld due to a valid Form W-4 not being on file. To make changes to your Federal or State Form W-4 employees may utilize Employee Self-Service in My.IllinoisState. Alternatively, hard copies of a completed Federal Form W-4 or Form IL-W-4 can be submitted to the University Payroll Office. Completed documents can be submitted electronically via the Secure Form Dropbox (Sensitive Form Submission)

A W-4 remains in effect until an employee submits a new one; except in the case where an employee claimed to be exempt or employment relationship has terminated. An exempt employee must complete a new W-4 each calendar year.

The W-4 for an employee who has indicated that he/she is exempt from withholding expires on February 15th of each calendar year. The ISU University Payroll Office will send notification in late January of each calendar year to employees who have completed their Form W-4's indicating that they are exempt from withholding. If the employee qualifies and wishes to continue being exempt from federal income tax withholding, the employee must complete a new Form W-4 and submit it the Payroll Office by the deadline indicated in the notification. To determine if you are eligible to claim exempt on your W-4, see the Exemption from Withholding section of IRS Publication 515.

If an employee is to receive an award payment or additional pay (i.e. overload pay, summer research, summer teaching), it is the responsibility of the employee to change their Form W-4 withholding status in order to prevent over taxation due to the additional income.

Federal Form W-4

For assistance in completing your Federal Form W-4, the IRS recommends individuals use the Tax Withholding Estimator.

Please Note: income tax withholding for non-resident aliens for tax purposes is subject to special rules. Individuals should consult with the TaxOffice@IllinoisState.edu prior to submitting income tax withholding forms.

Illinois Form W-4

To determine the correct number of allowances you should claim on your state Form IL-W-4, complete the worksheet on the back of the form to figure the correct number of allowances you are entitled to claim.

If you claimed exemption from withholding on Federal Form W-4, you still may be required to have Illinois income tax withheld.

Iowa Form W-4

To determine the correct number of allowances you should claim on your state Form IA-W-4, complete the worksheet on the back of the form to figure the correct number of allowances you are entitled to claim.

If you claimed exemption from withholding on Federal Form W-4, you still may be required to have Iowa income tax withheld.