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2023 Small Business Corporation Replacement Tax Forms

Name Description
IL-1120-ST 
Instructions
Small Business Corporation Replacement Tax Return (includes Schedule B)
IL-1120-ST-V  

Payment Voucher for Small Business Corporation Replacement Tax 

To make a return or extension payment, use this voucher and Appendix A of Form IL-1120-ST Instructions.
To make an estimated payment or voluntary prepayment, use this voucher and Appendix B of Form IL-1120-ST Instructions.

Important: Ensure the proper month and year of the filing period you wish to make a payment for is entered on the "Tax year ending" lines of the voucher.

IL-1120-ST-X
Instructions ​Amended Small Business Corporation Replacement Tax Return (includes Schedule B)
IL-1120-ST-X-V  

Payment Voucher for Amended Small Business Corporation Replacement Tax

Important: Ensure the proper month and year of the filing period you wish to make a payment for is entered on the "Tax year ending" lines of the voucher.

IL-477 Instructions Replacement Tax Investment Credits
IL-1000-E   Certificate of Exemption for Pass-through Withholding Payments
​IL-2220 Instructions ​Computation of Penalties for Businesses
IL-4562 Instructions Special Depreciation
Schedule F Instructions Gains from Sales or Exchanges of Property Acquired Before August 1, 1969
Schedule K-1-P 
  Partner's or Shareholder's Share of Income, Deductions, Credits, and Recapture
  Schedule K-1-P (1) Instructions for Partnerships and S Corporations Completing Schedule K-1-P and Schedule K-1-P(3)
  Schedule K-1-P (2) Partner's and Shareholder's Instructions
Schedule K-1-P (3)   Pass-through Withholding Calculation for Nonresident Members
Schedule M Instructions Other Additions and Subtractions (for businesses) 
Schedule NB Instructions Nonbusiness Income
Schedule NLD Instructions Illinois Net loss Deduction
Schedule UB
02/23/24 - Updated Step 2, Line 25, to reflect
federal Form 1120, Line 25 (Energy efficient
commercial buildings deduction).
Instructions Combined Apportionment for Unitary Business Group
Schedule 80/20 Instructions Related-Party Expenses
Schedule 1299-A

Instructions

07/10/24 – Updated to include new Quantum Computing Campuses tax credit.

Tax Subtractions and Credits (for partnerships and S corporations)

Schedule 1299-I

07/10/24 – Updated to include new Quantum Computing Campuses tax credit and to extend expiration dates for credits affected by recently passed legislation.

  Income Tax Credits Information and Worksheets
Schedule 4255

Instructions

Recapture of Investment Tax Credits
Subgroup Schedule (UB) Instructions Subgroup Schedule