Illinois vs Utah: state income tax, 2025
For reference household P1 (single, $60,000 of wages), Illinois charges $2,829or less and Utah charges $2,298or less. Both are bounded in the same direction, so the difference between them cannot be stated.
Both figures are a hypothetical full-year resident return for tax year 2025, over the same federal return, and count state income tax only. Neither is a relocation estimate: moving mid-year means two part-year returns, which this site does not figure. “Or less” means a mechanism the engine does not yet model would lower the figure; “or more” that it would raise it.
Six households, both states
| Household | Illinois | Utah | Illinois minus Utah |
|---|---|---|---|
| P1 Single, $60,000 of wages | $2,829or less | $2,298or less | not bounded |
| P2 Married filing jointly, $150,000, two children | $6,861or less | $6,083or less | not bounded |
| P3 Single, $85,000 wages + $15,000 long-term gain + $3,000 qualified dividends | $4,957or less | $4,635or less | not bounded |
| P4 Married retirees, $40,000 Social Security + $30,000 pension + $20,000 IRA, both 65+ | $0or less | $710or less | not bounded |
| P5 Head of household, $45,000, one child | $1,945or less | $538or less | not bounded |
| P6 Single, $1,200,000 of wages + $500,000 long-term gain | $84,150or less | $76,500or less | not bounded |
Full-year resident figures for 2025, state income tax only, with the same federal return in every column. Every figure is provisional. “Not shown” and “not figured” mean the engine will not state a number it cannot stand behind; hover for why.
Where the difference comes from
Illinois
- Where the return starts. Starts from federal adjusted gross income.
- Rate. A flat 4.95% on taxable income.35 ILCS 5/201; 2025 Form IL-1040 Instructions: "The Illinois income tax rate is 4.95 percent (.0495)." (checked 2026-08-05)
- Personal exemption. $2,850 per filer and $2,850 per dependant.35 ILCS 5/204; 2025 Form IL-1040 Instructions: "The personal exemption amount for tax year 2025 is $2,850." Line 10b and 10c each add $1,000 per box checked for age 65 or over and for blindness. (checked 2026-08-05)
- Excluded from income. Retirement income.2025 Form IL-1040 Instructions, Line 5: subtract federally taxed Social Security and retirement income from qualified employee benefit plans, IRAs and self-employed retirement plans reported on federal Form 1040 lines 4b and 5b, and Social Security and railroad retirement reported on line 6b. (checked 2026-08-05)
- Added to income. Municipal bond interest from other states.2025 Form IL-1040 Instructions, Line 2: add the federally tax-exempt interest and dividend income reported on federal Form 1040 line 2a. (checked 2026-08-05)
- Earned income credit. 20% of the federal credit, refundable.
Utah
- Where the return starts. Starts from federal adjusted gross income.
- Rate. A flat 4.5% on taxable income.Utah Code §59-10-104; 2025 TC-40 instructions line 10: "Multiply line 9 by 4.5 percent (.045)." (checked 2026-08-05)
- Personal exemption. $2,111 per dependant.Utah Code §59-10-1018(1)(g); 2025 TC-40 instructions line 11: "The Utah personal exemption is $2,111 per dependent." (checked 2026-08-05)
What this comparison leaves out
Mechanisms the engine does not model yet. Each one is named with the direction it would move the figure, which is where every “or less” above comes from.
Illinois
- Property tax and K-12 education expense credits (Schedule ICR) 35 ILCS 5/208, 5/201(m) — the figure is too high without it
- Illinois municipal bond and U.S. obligation subtractions (Schedule M) 35 ILCS 5/203(a)(2) — the figure is too high without it
- Credit for tax paid to another state (Schedule CR) 35 ILCS 5/601(b)(3) — the figure is too high without it
Utah
- Municipal bond interest addback (TC-40A Part 1) Utah Code §59-10-114(1) — the figure is too high without it
- TC-40A Part 2 subtractions — U.S. obligations, railroad retirement, previously-taxed retirement income Utah Code §59-10-114(2) — the figure is too high without it
- The other TC-40A Parts 3 and 4 nonrefundable credits — child tax credit, at-home parent, my529, military retirement, health benefit plan and the rest; and the earned income credit where no W-2 reports Utah wages in box 16 or the federal credit is undetermined Utah Code §59-10-1002.2, §59-10-1047, §59-10-1005, §59-10-1017, §59-10-1043, §59-10-1044 — the figure is too high without it
- Credit for income tax paid to another state Utah Code §59-10-1003 — the figure is too high without it
Taxes that are not income tax. Property tax, sales and excise taxes, and state payroll levies such as disability or paid-leave contributions are not counted here, and none of them is small. Federal tax is excluded because it is the same in both columns. A state income tax comparison is not a total tax burden comparison; see methodology.
Data status
Illinois. 2025 rules are provisional; engine coverage is implemented, with 3 mechanisms declared as not yet modelled. See the 2025 rate table.
Utah. 2025 rules are provisional; engine coverage is implemented, with 4 mechanisms declared as not yet modelled. See the 2025 rate table.
2026 state rules are not built yet, so this page compares 2025 only. Track status on the 2025 data status board.
Try it with your own return
The six households above are reference cases. Your own return will land differently. Compare Illinois and Utah over your own return — it stays in your browser.