How does FICA work on the Iowa paycheck?

FICA = Social Security + Medicare. Social Security is 6.2% of wages up to the 2026 wage base of $183,600 ($10,453 max). Medicare is 1.45% on all wages with no cap. An additional 0.9% Medicare applies to wages above $200,000 for single filers. The FICA stack is identical in all 50 states + DC — Iowa's state-level rules don't change FICA.

Does Iowa tax bonuses differently from regular paychecks?

Federal supplemental withholding on bonuses defaults to a flat 22% (or 37% above $1M annual). Iowa state withholding follows the state's supplemental rules: some states use the regular bracket; others use a flat supplemental rate. Year-end your actual tax liability is identical regardless of withholding method — the difference is whether you owe / refund at filing.

What about HSA, dependent care, or transit benefits in Iowa?

HSA contributions are pre-tax federally and FICA-exempt (one of the few benefits that reduces FICA), and pre-tax in most states except California and New Jersey (which tax HSA at the state level). Dependent Care FSA up to $5,000/year is pre-tax federally and state in most jurisdictions. Transit/parking benefits up to $315/month (2026) are pre-tax federally. The page calculator doesn't model these — apply them as pre-tax adjustments to gross.

Why does my actual Iowa paycheck differ from this calculator?

Common reasons: (1) you're not a single filer (married, head-of-household, MFS — the calculator uses single only); (2) you have pre-tax 401(k), HSA, FSA, or health-plan deductions reducing taxable wages; (3) your local city/county tax applies (calculator excludes those from the headline); (4) you have additional federal/state withholding selected on your W-4; (5) imputed income (group-term life over $50K, etc.) raises taxable wages above your stated salary.

What's the difference between marginal and effective tax rate in Iowa?

Marginal rate = the rate applied to your next dollar of income. Effective rate = total tax paid ÷ total gross income. In states with graduated brackets like California or New York, marginal can run 8-10% while effective at $100K is 4-6%. Iowa's structure: 3.8% flat (2026, SF 2417 fully phased) — see the income-tier reference table on this page for effective rate at each tier.

Does Iowa's flat tax apply to capital gains, dividends, retirement income?

Iowa flat-rate state tax generally applies to most W-2 wages, self-employment income, and ordinary investment income. Treatment of pensions, Social Security, IRA distributions, and capital gains varies — most flat-tax states tax these at the same flat rate as wages, but exceptions exist (e.g., PA exempts most retirement income from state tax entirely; IL exempts retirement). The calculator on this page applies to W-2 wage income.

What's the Iowa flat tax rate?

Iowa's state income tax structure: 3.8% flat (2026, SF 2417 fully phased) . The flat-rate model means your marginal and effective state-tax rates are identical at every income tier — a clean simplification compared with graduated-bracket states.

How Much Is My Paycheck After Taxes in Iowa? 2026 Calculator

TL;DR — Iowa take-home

Iowa taxes wage income at a single flat rate, so your effective and marginal state-tax rates are identical at every income tier. On a $100K gross the federal + state + FICA stack lands at $75,902.

Cost of living in Iowa runs below the national baseline (BEA RPP 88.8), which lifts the purchasing power of that $75,902 take-home to $85,505 in real terms — a meaningful arbitrage at this income tier.

Reference take-home table — Iowa (2026, single filer)

Gross W-2	Federal	State	FICA	Take-home	Effective rate
$40,000	$2,662	$922	$3,060	$33,356	16.6%
$60,000	$5,062	$1,682	$4,590	$48,666	18.9%
$80,000	$8,847	$2,442	$6,120	$62,592	21.8%
$100,000	$13,247	$3,202	$7,650	$75,902	24.1%
$130,000	$20,018	$4,342	$9,945	$95,696	26.4%
$160,000	$27,218	$5,482	$12,240	$115,060	28.1%
$200,000	$36,818	$7,002	$14,283	$141,897	29.1%

Standard deductions ($15,750 federal + state-specific 2026 figure) applied before bracket math. FICA = SS 6.2% to $183,600 + Medicare 1.45% (+0.9% above $200K). Local taxes (city/county) not in headline numbers.

How Iowa taxes work — 2026 structure

Flat-rate state income tax — same rate at every income tier

Iowa uses a flat-rate state income tax: 3.8% flat (2026, SF 2417 fully phased). The flat-rate model means your effective and marginal state-tax rates are identical at every income tier — a simplification compared with graduated states.

The state's 2026 standard deduction is applied before the flat rate. FICA stack is the same as everywhere else (SS + Medicare). Local-tax overlay applies on top of state in some jurisdictions — see the local section below if applicable.

Real take-home — Iowa cost of living adjusted

Metric	Iowa value
BEA Regional Price Parity (all-items, 2023)	88.8 (US = 100)
RPP — goods	96.6
RPP — rents	66.0
RPP — services	87.3
$100K gross take-home (nominal)	$75,902
Real take-home (purchasing power)	$85,505

Iowa sits below the national cost-of-living baseline (RPP 88.8), so a $75,902 nominal take-home expands to $85,505 in real purchasing power — a meaningful arbitrage at this income tier, particularly visible in rents at 66.0.

Compared with Iowa's neighbors at $100K gross

State	$100K take-home	Effective rate	Page
Iowa (this page)	$75,902	24.1%	—
Illinois	$74,153	25.8%	Illinois paycheck →
Minnesota	$73,754	26.2%	Minnesota paycheck →
Wisconsin	$74,891	25.1%	Wisconsin paycheck →
Missouri	$75,069	24.9%	Missouri paycheck →

Same single-filer assumptions across all rows. Federal + state + FICA only — local taxes not applied here.

Frequently asked — Iowa paycheck

How does FICA work on the Iowa paycheck?: FICA = Social Security + Medicare. Social Security is 6.2% of wages up to the 2026 wage base of $183,600 ($10,453 max). Medicare is 1.45% on all wages with no cap. An additional 0.9% Medicare applies to wages above $200,000 for single filers. The FICA stack is identical in all 50 states + DC — Iowa's state-level rules don't change FICA.
Does Iowa tax bonuses differently from regular paychecks?: Federal supplemental withholding on bonuses defaults to a flat 22% (or 37% above $1M annual). Iowa state withholding follows the state's supplemental rules: some states use the regular bracket; others use a flat supplemental rate. Year-end your actual tax liability is identical regardless of withholding method — the difference is whether you owe / refund at filing.
What about HSA, dependent care, or transit benefits in Iowa?: HSA contributions are pre-tax federally and FICA-exempt (one of the few benefits that reduces FICA), and pre-tax in most states except California and New Jersey (which tax HSA at the state level). Dependent Care FSA up to $5,000/year is pre-tax federally and state in most jurisdictions. Transit/parking benefits up to $315/month (2026) are pre-tax federally. The page calculator doesn't model these — apply them as pre-tax adjustments to gross.
Why does my actual Iowa paycheck differ from this calculator?: Common reasons: (1) you're not a single filer (married, head-of-household, MFS — the calculator uses single only); (2) you have pre-tax 401(k), HSA, FSA, or health-plan deductions reducing taxable wages; (3) your local city/county tax applies (calculator excludes those from the headline); (4) you have additional federal/state withholding selected on your W-4; (5) imputed income (group-term life over $50K, etc.) raises taxable wages above your stated salary.
What's the difference between marginal and effective tax rate in Iowa?: Marginal rate = the rate applied to your next dollar of income. Effective rate = total tax paid ÷ total gross income. In states with graduated brackets like California or New York, marginal can run 8-10% while effective at $100K is 4-6%. Iowa's structure: 3.8% flat (2026, SF 2417 fully phased) — see the income-tier reference table on this page for effective rate at each tier.
Does Iowa's flat tax apply to capital gains, dividends, retirement income?: Iowa flat-rate state tax generally applies to most W-2 wages, self-employment income, and ordinary investment income. Treatment of pensions, Social Security, IRA distributions, and capital gains varies — most flat-tax states tax these at the same flat rate as wages, but exceptions exist (e.g., PA exempts most retirement income from state tax entirely; IL exempts retirement). The calculator on this page applies to W-2 wage income.
What's the Iowa flat tax rate?: Iowa's state income tax structure: 3.8% flat (2026, SF 2417 fully phased). The flat-rate model means your marginal and effective state-tax rates are identical at every income tier — a clean simplification compared with graduated-bracket states.

Sources & methodology

Federal brackets — IRS Rev. Proc. 2025-32, 2026 single-filer tables, $15,750 standard deduction.
Iowa state brackets — 2026 Iowa Department of Revenue / Tax Foundation 2026 individual income tax structure summary. State standard deduction applied where relevant.
FICA — Social Security 6.2% on wages up to the 2026 wage base of $183,600; Medicare 1.45% on all wages; +0.9% Additional Medicare on wages above $200K (single filer).
BEA Regional Price Parities — 2023 vintage (all-items, goods, services, rents).
See the methodology · tax for full computation details and limitations.

By Marcus Liang · Founder & Editor · Last synced 2026-05-05.

Cross-state comparison: see how Iowa take-home ranks against the other 50 paycheck calculators on the Real Wage Atlas → — four-way ranking by real wage, after-tax take-home, state-tax savings, and cost-of-living arbitrage.