Illinois Payroll Tax and Registration Guide

To ensure your business remains compliant with state payroll tax regulations, you’ll need to gather and submit the following details before you can start processing payroll through Beyond:

  • State Employer Identification Number (EIN), along with any applicable state and local tax IDs
  • Assigned tax rates – Determined by state agencies based on your company’s structure, age, and size
  • Third-Party Authorization (TPA) and Power of Attorney (POA) – Required in most states so Beyond can file reports and remit tax payments on your behalf

 

Accurate and complete tax information must be provided and regularly maintained to allow Beyond to file and pay your company’s payroll taxes correctly. Beyond cannot be held liable for any fees, penalties, or interest that result from missing, incorrect, or outdated tax data.

Simplify State Tax Registrations with Middesk

Need help getting set up with state agencies? Beyond partners with Middesk to make it easier to manage your business's state registrations and stay compliant, no matter where your employees are located.

With Middesk, you can:
• Register for required tax IDs and agency accounts quickly and securely
• Manage all your state accounts through a single, user-friendly platform
• Track compliance and government correspondence directly from your dashboard
• Complete “foreign qualification” steps with the Secretary of State for multi-state compliance

Understand what you need to provide and what tax-related tasks Beyond takes care of for Hawaii employers

What Beyond Needs from You

All Illinois Employers

Task

Purpose

Register with the Illinois Department of Revenue

Enables your business to file and pay withholding taxes

Register with the Illinois Department of Employment Security (IDES)

Required to pay unemployment insurance

Submit your Illinois State Withholding Tax ID and deposit schedule

Issued by the Department of Revenue

Provide your Illinois Unemployment ID

Unique number tied to your IDES account

Submit your Illinois SUI (Unemployment Insurance) Rate

Sent annually by IDES and required to calculate contributions

What Beyond handles for Illinois employers

Withholding Tax

  • Form IL-501

    Withholding Payment Voucher - Submitted Semi-Weekly or Monthly

  • Form IL-941 & Schedule P

    Quarterly Withholding Reconciliation - Filed Quarterly

  • State W-2

    Wage and Tax Statement - Filed Annually

Unemployment Insurance Tax

  • IDES Form UI-3/40

    Illinois Quarterly Tax and Wage Report - Filed Quarterly

New Hire Reporting

  • Illinois New Hire Reporting Form

    Submission of Newly Hired Employee Information - As Required

Where to Find Your Tax Account Numbers

If your business already processes payroll in Illinois, you probably already have the necessary tax IDs. If you’re just getting started, here’s how to register:

Withholding Tax Account

Existing Employer:
Locate your account number on any IL-941 Withholding Income Tax Return, it should include your Federal EIN.

New Employer:
Register with the Illinois Department of Revenue via:

  • MyTax Illinois for fast online registration (usually processed within 1–2 days)
  • Form REG-1 by mail (available online or by calling 1-800-356-6302)
  • Use your Federal EIN to complete the registration; your state ID will incorporate it.

Unemployment Tax Account & Contribution Rate

Updated as of January 1, 2025

Existing Employer:
You’ll find your Illinois Unemployment Account Number and UI tax rate on the Notice of Contribution Rate mailed annually by IDES. Your rate is listed in the “contribution rate” box.

New Employer:
Register with the Illinois Department of Employment Security. Once approved, you’ll receive your Unemployment Account Number in a format like 1234567-8 or 1234567. This number is not your FEIN – and the last digit (check digit) may be omitted in IDES communications. If you don’t receive it, call IDES at (800) 247-4984.

  • The standard starting rate for new employers is 3.65%, with a taxable wage base of $13,916.

Have employees working in other states?

If your business operates across state lines or has remote team members based in different states, it’s essential to make sure the proper state paperwork is completed for each location. Beyond takes care of filing the necessary forms in every state where your employees are on payroll, helping you stay compliant no matter where your team works.