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How Bonuses Are Taxed in Iowa (2026)
A bonus paid on a separate check in Iowa has a flat 22% federal tax withheld (37% on cumulative supplemental wages over $1,000,000 in a year), 7.65% FICA, and Iowa's flat 3.8% state income tax. Withholding is not a higher tax rate — it is just how much your employer holds back up front; your actual tax on the bonus is settled when you file, and any over-withholding comes back as refund.
| Component | Rate on the bonus |
|---|---|
| Federal income tax (supplemental, percentage method) | 22% flat · 37% above $1,000,000/yr |
| Social Security | 6.2% (up to $184,500 of total wages) |
| Medicare | 1.45% · +0.9% above $200,000 |
| Iowa state tax | 3.8% flat |
Some employers instead use the aggregate method — adding the bonus to your regular paycheck and withholding as if that were every check — which can withhold more or less than the flat 22%. The calculator above uses the flat-rate (percentage) method.
Iowa Bonus Take-Home by Amount (2026)
Flat-rate (percentage) method, single filer, bonus paid separately on top of a $65,000 salary. Enter your own numbers in the calculator above — this table is a starting point.
| Bonus | Federal (22%) | FICA | Iowa tax | Take-home |
|---|---|---|---|---|
| $1,000 | $220 | $77 | $38 | $666 |
| $2,500 | $550 | $191 | $95 | $1,664 |
| $5,000 | $1,100 | $383 | $190 | $3,328 |
| $10,000 | $2,200 | $765 | $380 | $6,655 |
| $15,000 | $3,300 | $1,148 | $570 | $9,983 |
| $25,000 | $5,500 | $1,913 | $950 | $16,638 |
How Iowa Paycheck Tax Is Calculated (2026)
Source: Iowa Department of Revenue| Flat state rate | 3.80% |
|---|---|
| Standard deduction (single) | $16,100 |
Federal Tax & FICA (shared across all states)
| Filing status | Standard deduction |
|---|---|
| Single | $16,100 |
| Married Filing Jointly | $32,200 |
| Head of Household | $24,150 |
| Federal brackets (all filing statuses) | 10% / 12% / 22% / 24% / 32% / 35% / 37% |
|---|---|
| Social Security | 6.2% up to $184,500 wage base |
| Medicare | 1.45% on all wages, +0.9% above $200,000 single/HoH, $250,000 MFJ |
⚠️ Iowa's married-filing-jointly and head-of-household state brackets have not yet been independently verified against the primary source above — this calculator uses Iowa's single-filer brackets as an estimate when those statuses are selected.
Guideline version 2026-IA-v1 · Last verified 2026-07-26
Iowa Bonus Tax FAQ
What is Iowa's state income tax rate?
Iowa charges a flat 3.80% rate for tax year 2026. Standard deduction: $16,100 for single filers.
How much is take-home pay on $65,000 in Iowa?
On a $65,000 gross salary, a single filer in Iowa takes home roughly $52,549.3/year (about $4,379.11/month) after federal tax, FICA, and state tax.
What deductions does Iowa apply before taxing my income?
Iowa applies a $16,100 standard deduction, before the flat 3.80% rate. See the "How Iowa Paycheck Tax Is Calculated" section above for the exact formula.
Does this estimate change if I'm married or have dependents?
This calculator uses single-filer figures only (v1 scope). Married filing jointly typically uses different federal and Iowa state brackets and a larger standard deduction — your actual take-home pay will differ. Dependents can also reduce federal withholding via the W-4. Check Iowa Department of Revenue's married-filing-jointly tables for a precise figure.
Methodology & Source
Iowa state tax figures sourced from Iowa Department of Revenue (https://revenue.iowa.gov/), citing SF 2442 (2024) — flat 3.8% effective 2026, completing the phase-down from a 6-bracket system topping out at 8.53%. Federal brackets, standard deductions (single/MFJ/HoH), and FICA constants sourced from the IRS (Revenue Procedure 2025-32; married-filing-jointly Additional Medicare threshold of $250,000 is a separate, unindexed statutory figure). Iowa's married-filing-jointly and head-of-household figures are not yet independently verified and currently fall back to single-filer brackets — see the caveat in the formula section above.
Bonus federal withholding uses the flat supplemental-wage rate (22%, 37% above $1,000,000 cumulative supplemental wages/year), per IRS Publication 15 (Circular E), Employer's Tax Guide, 2026 edition — the alternative "aggregate method" is not modeled. Iowa publishes no separate supplemental withholding rate, so the calculator estimates the state tax on the bonus from your marginal bracket.
This is an estimate based on standard single-filer federal, FICA, and IA state calculations. Actual withholding may differ based on your W-4 elections, pre-tax deductions, and other factors.
Guideline version: 2026-IA-v1 · Effective: 2026-01-01 · Last verified: 2026-07-26