Illinois Individual Income Tax Forms(Tax Year 2025)
Illinois individual income taxes are administered by the
Illinois Department of Revenue.
This page provides official resources for Illinois individual income tax forms for tax year 2025, filed in 2026.
File Illinois Income Tax Online (2025)
Illinois provides electronic filing and payment through its official online system.
Taxpayers can file returns, make payments, and manage accounts using
MyTax Illinois.
Quick Links (Official Illinois Department of Revenue)
The official Illinois Department of Revenue website is available at
Illinois Department of Revenue.
General information about individual income tax is available on the
Illinois individual income tax overview page.
Official Illinois tax forms for all years are available in the
Illinois Department of Revenue forms library.
Illinois Individual Income Tax Forms (2025)
Illinois residents and nonresidents file their state income tax return using
Form IL-1040, Illinois Individual Income Tax Return.
Taxpayers who make estimated payments use
Form IL-1040-ES.
An extension of time to file may be requested using
Form IL-505-I.
Previously filed Illinois individual income tax returns may be corrected using
Form IL-1040-X, Amended Individual Income Tax Return.
Illinois Individual Income Tax Deadlines (Tax Year 2025)
Illinois individual income tax returns for tax year 2025 are due April 15, 2026.
Approved filing extensions generally run through October 15, 2026.
Estimated tax payments are generally due on April 15, June 15, September 15, 2026, and January 15, 2027.
Illinois Taxpayer Resources (2025)
Taxpayers can file returns and make payments using
MyTax Illinois.
Additional guidance is available on the
Illinois individual income tax guidance page.
Contact information for the Illinois Department of Revenue is available on the
official contact page.
Disclaimer
This page links to official Illinois Department of Revenue resources for informational purposes only.
Tax laws, forms, and filing requirements may change.
Always verify information on the official Illinois Department of Revenue website.
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