Iowa paycheck calculator, 2026
Iowa has been consolidating its rate schedule toward a flat structure, and withholding is computed from a formula with a standard deduction rather than a lookup table. The form asks for allowances, which reduce the taxable base. Our 2026 Iowa figures are still being cross-checked against the state publication, so this page shows the rules and sources rather than a take-home estimate.
The Iowa withholding rate, 2026
Iowa works this out from a formula rather than a bracket table, so the amount withheld depends on what your state form says as well as what you earn. These are the steps the calculation actually takes:
Bonuses and supplemental pay
Iowa withholds supplemental wages — bonuses, commission, severance — at a flat 3.8%, separately from your regular salary. A bonus can therefore have a different amount withheld than the same money paid as salary, which is usually why a bonus arrives smaller than expected.
What the Iowa withholding form asks for
| Field | What it does | Where it appears |
|---|---|---|
| Spouse has earned income | — | 2026 IA W-4 marital status section |
| IA W-4 annual allowance amount | Enter the dollar amount from IA W-4 line 6, not a count. | 2026 IA W-4, line 6 |
Notes and caveats
- The current Iowa formula is authoritative and supersedes NFC's older graduated formula. The state formula uses a flat 3.8% rate and does not subtract federal withholding.
Sources
Every figure on this page is transcribed from a published source and carries the date it was read. Where two sources disagree, the disagreement is recorded rather than resolved silently.
- Iowa Individual Income Tax Withholding Formula, effective January 1, 2026 — read 2026-07-19 · cross-checked against NFC Iowa formula (stale prior-law comparison)
- deduction — Iowa Individual Income Tax Withholding Formula, effective January 1, 2026 , Steps 1A and 1B · read 2026-07-19
This is an estimate of payroll withholding, not tax advice, and not a prediction of your final tax bill. Withholding is what your employer sends in during the year; what you actually owe is settled when you file.