Illinois Department of Revenue Alerts Taxpayers to Common Errors to Avoid When Preparing Tax Returns

CHICAGO – The Illinois Department of Revenue (IDOR) is advising taxpayers to be vigilant when preparing tax returns in order to avoid several common errors which can lead to delays, rejections, or even penalties.

“We encourage taxpayers to file electronically and review their information carefully in order to ensure their returns are complete and accurate,” said` IDOR Director David Harris. “Mistakes on returns can have negative consequences, such as delays in processing refunds, or even the rejection of returns.”

Common Filing Errors to Avoid

• Incorrect Personal Information - Double-check names, Social Security numbers, and dates of birth to ensure they match the information on file with the Social Security Administration.
• Missing or Incorrect Bank Account Information - Taxpayers expecting refunds should choose direct deposit to their bank accounts to get refunds promptly. They should verify their account and routing numbers and ensure the correct information is entered on their returns.
• Failure to Report All Income - Taxpayers are required to report all sources of income including wages, dividends, freelance work, and investment earnings. Underreporting income can result in penalties and interest charges.
• Incorrect Filing Status - Wrong filing status can have significant consequences on tax liability and refunds.
• Mathematical Errors - Tax returns that include basic math errors, especially in calculations of credits, deductions, or taxable income, are flagged, resulting in delays.
• Missing Deductions or Credits - Taxpayers may be eligible for various tax deductions and credits. Failure to claim these credits or deductions can have taxpayers paying more tax than they really need to.
• Not Signing or Dating Returns - Unsigned or undated tax returns are considered incomplete.
• Filing Paper Returns Too Late - Paper returns take longer to complete and process, and delays can result in missing the filing deadline. IDOR recommends filing electronically for faster processing.
• Incorrect or Missing Tax Preparer Information - Taxpayers using a tax preparer need to make sure their Preparer Tax Identification Number (PTIN) and contact information is correctly listed on returns.

Filing Returns

Illinois is participating in the Internal Revenue Service (IRS) Direct File program this year. Eligible taxpayers can use the program to electronically complete their 2024 federal tax returns for free. Eligibility can be confirmed by visiting https://directfile.irs.gov .

After using Direct File to file a federal return, the program will connect taxpayers to Illinois’ free state income tax filing system, MyTax Illinois, where they can file and complete their Illinois state returns. Individuals may also choose to file using tax-prep software, a tax professional, or the paper Form IL-1040.

If a taxpayer electronically files an error-free return, they should receive a direct deposit refund in approximately four weeks.

The tax filing deadline is Tuesday, April 15, 2025.

To receive assistance taxpayers may call 1-800-732-8866 or 217-782-3336. Free language assistance for Limited English Proficiency (LEP) individuals is available. For the most up-to-date information, forms, schedules, and instructions for the 2025 tax season, taxpayers may visit IDOR's website at tax.illinois.gov.

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