Illinois Forms
Find Illinois state forms for tax, business, vehicle, employment, and other government filing workflows with fillable PDFs and source-backed form pages.
Find the right Illinois form
Browse state-specific form pages for tax, business, vehicle, and government workflows. Each listing is filtered through DocuHub quality checks before it appears in indexable catalog pages.
Before filing
- Confirm the Illinois agency, tax year, or form revision before filing.
- Check state instructions for fees, filing addresses, e-file options, and supporting documents.
- Use the official state source for final deadlines, eligibility rules, and submission requirements.
7 Illinois Forms
Page 1 of 1
IL-1040 (Illinois)(2024)
Individual Income Tax Return
Illinois individual income tax return for full-year and part-year residents. The primary form for filing Illinois state income taxes.
IL-1040-ES (Illinois)(2024)
Estimated Income Tax Payment
Illinois estimated income tax payment voucher for individuals making quarterly estimated tax payments.
IL-1040-X (Illinois)(2024)
Amended Individual Income Tax Return
Illinois amended individual income tax return for correcting previously filed IL-1040 returns.
IL-2210 (Illinois)(2024)
Computation of Penalties for Individuals
Illinois form for computing penalties for underpayment of estimated individual income tax.
IL-505-I (Illinois)(2024)
Automatic Extension Payment
Illinois automatic extension payment voucher for individual income tax. Used to make a payment with an extension request.
Illinois LLC Formation(2025)
Illinois LLC Articles of Organization
Illinois Secretary of State form for forming a limited liability company.
Schedule IL-E/EIC (Illinois)(2024)
Illinois Exemption and Earned Income Credit
Illinois schedule for claiming personal exemptions and the Illinois Earned Income Credit on the IL-1040.