Illinois R&D Tax Credit Summary

R&D Tax Credit Available:


Eligible Entities:

C-Corporations, S-Corporations, LLCs, Partnerships

Deadline for Tax Filing:

Due with Illinois Tax Return

Data Required to Compute Credit:

  • Claim Period Qualified R&D Expenses (QREs)
  • QREs for Prior 3 Years

Credit Carryforward:

5 Years

R&D Credit Summary:

The R&D tax credit equals 6.5% on the excess of IL qualified research expenses over the average amount of QREs for the three preceding taxable years.

Special Notes:

The Illinois research credit expires on December 31, 2021.

Research Tax Credit
Important Links and Forms

Schedule 1299-D
Instructions for 1299-D
Schedule 1299-I

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