What payroll deadlines should employers track?

Illinois Payroll Tax Deadlines Employers Must Track

Employers operating in Illinois need to stay on top of various payroll tax deadlines to ensure compliance and avoid penalties. Managing these deadlines efficiently supports smooth payroll processing, accurate tax reporting, and proper bookkeeping.

Key Payroll Tax Deadlines in Illinois

• Federal Payroll Tax Deposits: Employers must deposit federal income tax withheld, Social Security, and Medicare taxes according to their IRS deposit schedule—either monthly or semi-weekly. These deadlines are critical to avoid federal penalties.
• Illinois Withholding Tax: Illinois requires employers to remit state income tax withheld from employee wages. Deposits are typically due either monthly or quarterly, based on the amount of tax withheld. As of 2026, most employers file and pay Illinois withholding tax electronically through the Illinois Department of Revenue (IDOR) system.
• Illinois Unemployment Insurance (UI) Contributions: Employers must submit UI tax payments quarterly. The due dates are typically the last day of the month following the end of each calendar quarter (April 30, July 31, October 31, and January 31).
• Quarterly Payroll Tax Reporting: Employers must file federal Form 941 quarterly to report income taxes, Social Security, and Medicare taxes withheld. Illinois employers also file quarterly withholding returns with the state.
• Annual Payroll Tax Filings: Employers must file federal Form W-2 for each employee and submit copies to the Social Security Administration by January 31. Illinois also requires submission of W-2 copies to the state by the same deadline.

Operational Tips for Managing Payroll Deadlines

• Automate Reminders: Use payroll software or calendar tools to track federal and Illinois-specific tax deadlines to prevent missed payments.
• Leverage Electronic Filing: Illinois encourages electronic payments and filings through the MyTax Illinois portal to streamline compliance and reduce errors.
• Maintain Accurate Records: Keep detailed payroll records, including tax deposits and filings, to support audits and reporting requirements.
• Coordinate with Payroll Service Providers: If outsourcing payroll, confirm your provider’s schedule aligns with Illinois and federal deadlines.
• Stay Updated: Payroll tax laws and deposit schedules can change. Regularly review guidance from the Illinois Department of Revenue and the IRS.