Chicagoland CPA: Tax, Payroll and Accounting Services

Chicagoland is the Chicago metropolitan area, and for tax purposes it is really a patchwork. Within a one-hour drive you can cross from Cook County, with its own assessor and Board of Review, into DuPage, Will, Kane, Kendall or Lake counties, each with its own property tax offices, and into dozens of cities and villages that set their own local taxes. Our firm is based in Naperville and serves clients across this region in person by appointment or entirely online. This page is a map: where the counties and cities fall, what changes from place to place, and what stays the same.

The counties and who handles property tax

Illinois bills property tax a year in arrears. The collar counties generally mail a single bill in the spring with two installments in the summer and early fall, and each publishes its own dates. Cook has been different. On the Cook County Treasurer's due-dates page, the second installment for tax year 2023 was due August 1, 2024, for tax year 2024 it was December 15, 2025, and for tax year 2025 it is October 1, 2026. Always read the dates for your own bill instead of assuming last year's calendar.

Cook also runs on a triennial reassessment cycle: the Assessor reassesses about one-third of the county each year, and the north and northwest suburbs, which include Schaumburg, were reassessed in 2025. The Assessor publishes a calendar with each township's notice and appeal dates. An assessment appeal challenges your assessed value, not the bill itself, and the windows are set township by township.

Cities we cover, by county

Cities near county lines can sit in more than one county. The counties below come from the Census Bureau's 2020 place-by-county list. The notes are verified local details from each page.

What is the same everywhere

• Income tax. Illinois taxes individuals at 4.95 percent of net income. Residents can subtract federally taxed Social Security and certain retirement income. See our Illinois guide.
• Sales tax. The State rate on general merchandise is 6.25 percent. Local taxes are added on top, and the Department of Revenue's Tax Rate Finder gives the rate for a given address and period. The rates change on January 1 and July 1.
• Business taxes. Corporations pay a replacement tax of 2.5 percent of net income, while partnerships, trusts and S corporations pay 1.5 percent. Partnerships and S corporations can elect an entity-level 4.95 percent tax, which affects the entity choice.
• Employers. Employers register with IDES and file unemployment insurance reports quarterly. See state unemployment insurance.

What changes from place to place

Municipalities decide whether to charge a food and beverage tax, a hotel tax, an amusement tax or a real estate transfer tax, and home rule units can impose a home rule sales tax collected by the State. Chicago has the longest list, and some suburbs have almost none. Oak Brook reports no village property tax levy, while Romeoville and Montgomery run village property tax rebate programs. Employers in Chicago and Cook County also face local paid leave ordinances that sit alongside the state Paid Leave for All Workers Act.

Working with us across Chicagoland

We prepare individual and business returns, run payroll, keep books, form entities and handle IRS notices. Several western and northwestern suburbs have large Indian-American communities. In the Census Bureau's 2020-2024 estimates, about 13 percent of residents of both Naperville and Schaumburg identified as Asian Indian alone, and about 17 percent in Oak Brook. We help with NRI and US-India tax questions for these households and for clients anywhere else. Visit our contact page to set up an appointment.

Frequently asked questions

General information only, not tax, legal or accounting advice for your situation. Rules, limits and deadlines change; confirm the current rules with the official source or a qualified professional before you act. Reading this page does not create a professional relationship with CPA Tax Payroll and Accounting Corp.