Jurisdiction detail

Illinois tax guide

A seeded subnational profile for Illinois, built on the schema from the world-class expansion plan.

Country

United States

Tax year

2026

Authority

Illinois Department of Revenue

Overview

Illinois has a flat personal-income tax but adds a 2.5 percent Personal Property Replacement Tax to its corporate rate. Chicago home-rule sales-tax additions and high property-tax burdens are distinctive.

PPRT applies to corporations, partnerships, S corps, and trusts.Illinois has its own pass-through entity tax (PTET) election.Chicago has additional local taxes on amusement, lease, and other categories.

Individual income tax

Illinois imposes a flat 4.95 percent individual income tax.

Type: flat

Business tax

Combined effective corporate rate includes 7.0 percent income tax plus 2.5 percent Personal Property Replacement Tax (PPRT).

Reference rate: 9.5%

Sales or indirect tax

Economic nexus applies for remote sellers.

Base rate: 6.25%

Local home-rule add-ons can push combined rates above 10 percent in Chicago.

Deadlines and forms

Individual returns due April 15; corporate returns the 15th day of the 4th month after year-end.

Official authority

Visit Illinois Department of Revenue

Primary sources

Illinois Department of RevenueVerified 2026-05-20

Important disclaimer

This library is for general tax education only. Always verify filing obligations, due dates, and tax consequences against the cited primary source or with a qualified tax professional.