📝 Overview
This guide covers state tax information for employers running payroll in Illinois. Use the sections below to find agency contact information, supported tax filings, and the account details required for tax setup.
⚙️ Illinois Tax Information
Click the arrow to view Withholding information
Click the arrow to view Withholding information
Agency Information
Website: Illinois Department of Revenue
Phone: (217) 782-3336
Supported Tax Filings
Withholding Income Tax Return (IL-941)
Wage & Tax Statement (W-2)
Nonemployee Compensation (1099-NEC)
Required for Tax Setup
Withholding Account Number (12 digits, e.g., 12-3456789 123)
Deposit Schedule (Semi-weekly or Monthly)
Third Party Administrator (TPA) Access
DaySmart Payroll needs granted TPA access to pay and file this tax. Follow the instructions below to ensure there are no delays in processing:
Log in to MyTax Illinois
In the top right corner, select the name shown on the account
Select Manage My Profile
Select the More tab
In the Access section, select Manage Third Party Access
Under Third Party Access, confirm the following settings:
Allow: Yes
Default access: Third Party
Default account access: Full Access
⚠️ If the Allow field is set to No, DaySmart Payroll will not be able to manage tax filings on your behalf. Confirm all three settings are correct before leaving this page.
Click the arrow to view Unemployment Insurance information
Click the arrow to view Unemployment Insurance information
Agency Information
Website: Illinois Department of Employment Security
Phone: (800) 247-4984
Supported Tax Filings
Employer's Contribution and Wage Report (UI-3/40)
Required for Tax Setup
Unemployment Account Number (7–8 digits, e.g., 1234567 or 1234567-8)
Contribution Rate (X.XX%)
❓ Frequently Asked Questions (FAQs)
Find answers to common questions or additional details that may not be covered in the main instructions.
Click the arrow to view frequently asked questions
Click the arrow to view frequently asked questions
Where do I find my Illinois withholding account number?
Click the arrow to see the answer
Click the arrow to see the answer
Your Illinois withholding account number is a 12-digit number formatted as 12-3456789 123. It is assigned by the Illinois Department of Revenue when you register and can be found on agency correspondence or by logging into your MyTax Illinois account.
How do I find my Illinois unemployment account number and contribution rate?
Click the arrow to see the answer
Click the arrow to see the answer
Your unemployment account number is assigned by the Illinois Department of Employment Security when you register. Your contribution rate is included in an annual rate notice from the agency. Both can also be found by logging into MyTax Illinois or by contacting IDES at (800) 247-4984.
How do I determine my Illinois withholding deposit schedule?
Click the arrow to see the answer
Click the arrow to see the answer
Your Illinois deposit schedule (Semi-weekly or Monthly) is based on the total amount of withholding tax you remit during a lookback period, following a similar approach to the Federal deposit schedule. The Illinois Department of Revenue will assign your schedule, and you can confirm it by logging into your MyTax Illinois account or contacting the agency at (217) 782-3336.