Iowa income tax goes up to 3.8% at the top bracket. Calculate your combined federal + state effective tax rate for 2026. Formula shown, sources cited — no account required.
The state now uses a flat income tax rate of 3.8% on all taxable income, a significant simplification from the multi-bracket system that was in place for decades. This flat structure means every earner — from entry-level workers to top executives — pays the same marginal rate, and there are no thresholds to plan around. For the median earner at $75,501, state income tax comes to about $2,869 before applying any deductions or credits. Federal taxes stack on top at graduated rates, and the combined effective rate for a median household typically falls in the low-to-mid twenties. One of the most notable state features for tax planning is the complete retirement income exemption for residents 55 and older — Social Security, pensions, and all retirement account withdrawals are excluded from state taxable income. That exemption dramatically changes the after-tax picture for retirees compared to working-age residents. Younger workers accumulating savings should note that contributions to retirement accounts follow standard federal rules, with no additional state-level deduction beyond what federal law provides. Use the tax bracket calculator to compare your effective rate at your actual income.
Iowa Tax Brackets Explained (2026)
Iowa has a state income tax with a top marginal rate of 3.8%. On top of federal rates (10%–37%), residents can face a combined marginal rate exceeding 35% at higher income levels. However, your effective rate is always lower than the marginal rate because only income above each threshold is taxed at that bracket's rate.
The median household in Iowa earns $75,501/year. At that income (single filer), the federal effective rate is approximately 12–14%, bringing total income tax (federal + state) to roughly 14–17%.
How Marginal vs. Effective Rate Works
The marginal rate is the rate on your last dollar of income — it does not apply to all income. The effective rate is your total tax divided by total income. For example, someone earning $100,000 in Iowa has a 22% federal marginal rate but an effective federal rate of roughly 15%, because the first $44,725 (2024) is taxed at 10% and 12%, not 22%.