Illinois · research and development · IL-RD-001
Research and Development Credit
Publication revised September 24, 2026. Sourcebook page 103.
Credit amount / calculation
6.5% of qualifying Illinois research and development expenditures over the three-year base-period average under current law.
Business fit and eligible activity
Qualified Illinois research can generate an incremental income-tax credit. Qualified research activity. Ordinary production, routine quality control and an equipment purchase alone do not qualify.
Eligibility and practical use
For forest products, research credits usually live on the mill floor rather than in a laboratory. Scanner settings, drying schedules, process-control changes, product testing, and equipment modifications can matter when the work is experimental rather than routine. A logging company has a narrower path, but equipment-control, software, or process-development work can sometimes qualify if it satisfies the same technical tests.
Illustrative business benefit
A hardwood mill spends $320,000 on a documented project to improve recovery from low-grade logs using scanner changes, controlled test runs, software adjustments, and revised sawing patterns. Assume $200,000 is ultimately treated as the relevant qualified or excess research base. At 6.5%, the state credit would be about $13,000 before program caps and tax-liability limits. The company would need records showing the uncertainty, alternatives tested, people involved, and results - not simply a year-end estimate of 'engineering time.'
Timing / first action
Tax-year claim: document the eligible expense, hire or placed-in-service date and meet any separate certification deadline. Identify the technical uncertainty and start contemporaneous project records before trying to calculate the credit.
Official sources
Related programs
Apprenticeship Education Expense Credit
up to
Employers supporting qualified apprentices may claim education-expense credits.
EDGE Tax Credit
generally
Manufacturers expanding in Illinois may receive a negotiated payroll-based credit if job, investment and strict 'but-for' rules are met.
Historic Preservation Tax Credit
Credit based on qualified rehabilitation expenditures
Certified historic industrial properties can qualify for a state rehabilitation credit.
Clean Electricity Investment Credit (Internal Revenue Code §48E)
Generally
Potentially relevant when a forest-products facility owns qualifying zero-emission generation or energy-storage property.
Credit for Increasing Research Activities (Internal Revenue Code §41)
Regular research-credit method
A sawmill, secondary manufacturer or biomass business can qualify when it performs genuine technological experimentation to improve a product or process.
Rehabilitation Credit (Internal Revenue Code §47)
Generally
A forest-products company rehabilitating a certified historic mill or industrial building for income-producing use may qualify.