Illinois' Tax Load: A Flat Income Tax, a High Sales Tax, and a Tale of Two Markets
Illinois sits at a Regional Price Parity of 98.9, which measures how its overall price level compares with the U.S. average of 100. that single number quietly drives everything else in a Illinois household budget — from the rent you can afford to how far a paycheck stretches.
Income- and sales-tax figures: Tax Foundation — State Individual Income Tax Rates & Brackets (2025).
Where the Dollars Go: Rent City by City in Illinois
Illinois uses a flat 4.95% individual income tax and a 6.25% state sales-tax base that local add-ons commonly push past 10% at the register in Chicago. The cost base is just below the national average, but the divide between Chicago and downstate is enormous.
As of 2025, Chicago one-bedrooms average roughly $2,400 (ApartmentAdvisor) with two-bedrooms near $2,800, while HUD Fair Market Rent puts the Chicago metro one-bedroom at $1,560 and two-bedroom at $1,761. Downstate is far cheaper: Springfield one-bedrooms average about $921 (FMR) to $955, Peoria $790, and Rockford $900. A two-bedroom in Springfield runs about $1,132.
Because the gap between Chicago and a downstate city can exceed $1,400 a month for the same apartment size, your Illinois budget is really two different budgets depending on the metro.
Rent ranges reflect 2025 listings aggregated by Apartments.com and HUD Fair Market Rents via RentData. RPP: BEA Regional Price Parities (2023).
What $3,800 Really Buys in Illinois
At the national average price level, $3,800 a month covers a fixed basket of rent, food, transport, and bills for a typical Illinois household. In Illinois, where the RPP is 98.9, that same basket costs about $3,758 — roughly 1% below the national average for identical things. Flip it around and $3,800 earned and spent in Illinois behaves like about $3,842 of purchasing power at the national average. The gap is gentle, which shapes who can comfortably live in Illinois.
Use the Illinois relocation calculator below to substitute your own figures; it scales any budget by the RPP ratio so you never do the math by hand.
Rent or Own in Illinois
Illinois tilts toward owning downstate and renting in Chicago. The Chicago median home price is high, while downstate medians are modest and property taxes are notoriously elevated statewide — a quiet hit to owners. Renters trade flexibility for Chicago's premium, but with one-bedrooms under $950 in Peoria and Springfield, downstate renting stays cheap while you save.
Help Is Available: Illinois Assistance You Can Budget Around
Illinois runs a mix of federal and state household aid, but a realistic budget should treat these as real line items:
- SNAP (food assistance). Federal maximums apply — about $292 a month for one person and $535 for a household of two (FY2025) — administered by the Illinois Department of Human Services.
- All Kids / Illinois Medicaid. The state's CHIP-plus-Medicaid coverage for children and expanded adults — a major line in a family budget.
- Illinois LIHEAP. Federal heating assistance helps with brutal winter bills — meaningful given Illinois' long cold season.
- IHDA homebuyer programs. The Illinois Housing Development Authority runs down-payment and first-time-buyer assistance that can cut thousands off a purchase.
- Earned Income Tax Credit. Illinois boosts the federal EITC at the state level, putting real cash back into low-to-moderate incomes each filing season.
Program rules change yearly. Confirm current figures with USDA SNAP, LIHEAP, and Illinois state agencies.
Who Thrives in Illinois — and Who Feels the Squeeze
Thrive: remote workers earning an out-of-state salary, homeowners outside Cook County's highest-tax townships, and downstate renters where one-bedrooms stay under $950. Get squeezed: Chicago renters facing $2,400+ one-bedrooms; suburban owners hit by high property taxes; and anyone who forgets the 10%+ combined sales tax at Chicago checkout.
Budgeting That Works in Illinois
Start with the flat 4.95% income tax and the 6.25% base sales tax plus local add-ons — in Chicago build a double-digit checkout buffer into "needs." In Illinois, cap rent near 28% of gross income, automate savings, and run your real numbers through the monthly-budget calculator before signing a lease. Pull your last three months of statements and match them to Illinois' real prices with the calculators here.
Illinois vs Its Neighbors
For context, Illinois is framed by its neighbors: Indiana sits at RPP 92.2 with a flat 3.00% income tax and a 7.00% sales tax, while Missouri sits at RPP 91.8 with a top income rate of 4.70% and a 4.225% sales tax. Against those neighbors, Illinois (RPP 98.9, flat 4.95% income, 6.25% sales) is the pricier place to live but offers a lower sales-tax ceiling than Indiana. Weigh Illinois' full package — not just the income-tax line — when judging a move.