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State Tax Savings and Exposure Calculator
Enter your income and pick two states. See the estimated state income tax delta from 2026 bracket data, then see what it actually takes to make that savings survive an audit.
General information, not tax or legal advice. See methodology and sources below.
Calculator
Compare state income tax between two states.
Leaving Illinois
$12,375
estimated annual state income tax
Illinois taxes income at a flat 4.95% rate after its standard deduction.
Marginal rate: 4.95% · Effective rate: 4.95%
Moving to Alaska
$0
estimated annual state income tax
Alaska has no state individual income tax on wages, salaries, interest, dividends, or capital gains.
Marginal rate: 0% · Effective rate: 0%
Moving from Illinois to Alaska would save an estimated $12,375 per year in state income tax at this income.
That is roughly $1,031 per month at this income and filing status.
Savings only survive an audit you can win.
Illinois does not use a fixed day count. It weighs a closest-connections and domicile test instead. Here is what Illinois would need to see before an exit claim survives an audit.
Illinois is not in the top tier of aggressive exit-audit states the way New York or California are, but the Department of Revenue does examine departing high earners, especially where a large capital gain or business sale occurred near the claimed move date, or where the taxpayer kept an Illinois home, spouse, or business presence after claiming nonresidency. Auditors reconstruct day counts using credit card statements, toll records, airline records, and utility usage, and they cross-check the General Homestead Exemption against a claimed out-of-state domicile.
Statute of limitations
Generally 3 years from the later of the return's due date or filing date. This extends to 6 years if 25% or more of income was omitted from the return. There is no statute of limitations for fraud or for a return that was never filed, except that a voluntarily disclosed non-filed return can generally be assessed up to 4 years after the original due date.
Defense cost range
No published statewide figures exist for the cost of defending an Illinois residency audit. Because Illinois residency disputes are less frequently litigated to published decision than New York's or California's, practitioners generally decline to give a specific range and instead price engagements case by case based on the number of years and the complexity of the day-count reconstruction involved.
What Illinois checks
Common exit mistakes
Popular corridors
California to Arizona
Load this comparisonCalifornia to Colorado
Load this comparisonCalifornia to Florida
Load this comparisonCalifornia to Idaho
Load this comparisonCalifornia to Nevada
Load this comparisonCalifornia to Puerto Rico
Load this comparisonCalifornia to Tennessee
Load this comparisonCalifornia to Texas
Load this comparisonHow the estimate is built
Each state's bracket schedule, standard deduction, and no-tax or flat-tax status come from data/residency/tax-tables.json, a 2026 tax year table compiled 2026-08-05 and sourced primarily from the Tax Foundation, cross-checked against state revenue agency pages.
The calculator subtracts the standard deduction from your entered income, then applies the state's marginal bracket schedule (or its single flat rate, or $0 for the nine states with no income tax) to what remains. It does not model itemized deductions, credits, local income taxes, or capital gains treatment that differs from ordinary income.
Puerto Rico, the U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands run regimes that cannot be reduced to a single bracket rate honestly, so the calculator explains why instead of guessing.
Why the exposure panel matters
A lower number on a calculator only becomes real money if your former state agrees you actually left. High-tax states with aggressive enforcement audit departing high earners on domicile, not just day counts: family location, retained property, financial relationships, and the timing of the move relative to a liquidity event.
The exposure panel pulls your origin state's exit audit risk, enforcement methods, common exit mistakes, statute of limitations, and audit aggressiveness directly from its researched dossier, the same data behind the full state guide.
See all 56 state and territory guidesFrequently asked questions
How accurate is this state tax calculator?+
The calculator applies each state's actual published 2026 income tax brackets and standard deduction from data/residency/tax-tables.json, sourced primarily from the Tax Foundation and cross-checked against state revenue agency pages. It is a planning estimate, not a filing: it does not account for itemized deductions, credits, local or city income taxes, or income other than ordinary wage-style income.
Does this include local or city income taxes?+
No. The figures shown are state-level income tax only. Some cities layer their own income tax on top of the state figure (New York City is the best-known example), so your actual bill in a city with a local tax will be higher than what this tool shows.
Why can't I get a dollar estimate for Puerto Rico, Guam, or the other territories?+
The five U.S. territories do not run state-style bracket tables. Puerto Rico has its own separate tax code plus a decree-based Act 60 incentive program, and the U.S. Virgin Islands, Guam, and the Northern Mariana Islands mirror the federal code with local filing instead of state brackets. Reducing any of these to one calculator rate would misstate the actual regime, so the tool shows an honest explanation instead of a fabricated number. Use the jurisdiction guide for the real rules.
If the calculator shows savings, is that savings guaranteed?+
No. A state income tax bill only drops if your residency change actually holds up under audit. States with aggressive enforcement, especially high-tax states losing a high earner, look closely at whether your domicile genuinely moved: where your family lives, where you spend your time, and whether you kept ties like a home, doctors, or bank relationships behind. That is what the exposure panel below the calculator explains for your origin state.
Does this account for capital gains, stock options, or business income?+
The calculator applies each state's general income tax brackets, which most states tax the same as ordinary income (a few exceptions are noted on the state guides). It does not model deferred compensation, stock vesting schedules, or business income sourcing rules, all of which several states keep taxing after you leave under trailing-income rules. Check your origin state's guide for its specific trailing-income treatment before assuming a move date changes when that income is taxed.
What income figure should I enter?+
Enter your expected annual gross income (wages, salary, and similar ordinary income). The calculator subtracts each state's standard deduction automatically to estimate taxable income, then applies that state's bracket schedule. It does not know about your itemized deductions, pretax retirement contributions, or credits, so treat the result as a starting estimate rather than a completed return.
Methodology and sources
Tax figures: 2026 state individual income tax brackets and standard deductions from data/residency/tax-tables.json, compiled 2026-08-05, sourced primarily from the Tax Foundation's state income tax rates publication and cross-checked against individual state revenue agency pages.
Exposure figures: each state's exit audit risk, enforcement methods, statute of limitations, and audit aggressiveness come from that state's researched dossier at data/residency, with sources listed on the corresponding state guide.
ResidencyIQ organizes public tax and residency research into a reviewable estimate. It does not provide legal, tax, or accounting advice. Consult a qualified professional before making a residency decision or filing a return.
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