What if?
The same sale under different choices, each computed by the engine rather than estimated. Figures are the tax on the gain, so the rows stay comparable when a variant spans two tax years. Select one to load it into the calculator and read its full derivation.
Estimates only — this is not tax advice. Consult a CPA or enrolled agent before acting on these figures. The calculator does not model the alternative minimum tax, wash sales, like-kind exchanges, QSBS, installment sales, or state additions and subtractions. See what is out of scope.
Show your work — 0 steps, each with its rule and citation
How Iowa taxes a capital gain
Statutory authority: Iowa Code 2026, section 422.5(1)(a) (retrieved 1 September 2026)
A flat rate, from the current edition of the code
Iowa completed a multi-year move from a graduated schedule to a single flat rate, and the 2026 edition of the Iowa Code states it directly: a tax is imposed upon every resident and nonresident of the state at a rate of three and eight-tenths per cent.
The edition matters as much as the section. State codes are republished annually, and an older edition of the same section carries the older ladder without announcing that it has been superseded. The figure on this page comes from the edition that governs tax year 2026, which is why the citation names it.
For capital gains the flat structure means the state layer is simply the gain multiplied by the rate. There is no bracket to straddle and no dependence on the size of your other income, which makes Iowa unusually predictable to plan around.
Iowa has capital-gains deductions, and this calculator does not apply them
Iowa is one of a small group of states that grant a deduction aimed specifically at capital gains, and the omission is disclosed here because assuming otherwise would overstate the tax for the people it covers.
The deductions are narrow rather than general. They reach retired farmers selling farm property, and capital gain from the sale of stock in a qualifying Iowa-based employee-owned company. Both come with conditions on the taxpayer and on the asset that this calculator has no way of knowing from the inputs it collects.
What they do not reach is an ordinary sale of listed securities or a second home, which is the overwhelming majority of what people bring to a capital gains calculator. So the figure here is correct for a typical investment sale and too high for a qualifying farm or employee-ownership disposal — and if you are in the second group, this is the point at which to involve a preparer rather than a calculator.
No preferential rate for holding an asset longer
Beyond those specific deductions, Iowa gives capital gains no preferential treatment. A long-term gain and a short-term gain of the same size attract the same 3.8%, and a gain attracts the same rate as a paycheque. The distinction between eleven months and thirteen months is worth a great deal federally and nothing at the Iowa state level.
Iowa also adjusts for gains and losses on the sale of gold and silver bullion, which are added back or subtracted from federal income under separate legislation. That treatment is not modelled here either.
Which Iowa sales the deduction reaches, and which it does not
The distinction is worth drawing carefully, because "Iowa has a capital gains deduction" is true and, stated without qualification, misleading for almost everyone who reads it.
The deduction is tied to the character of the asset and the taxpayer rather than to the gain itself. The farm provisions turn on material participation and on the taxpayer having retired or being disabled; the employee-ownership provision turns on the stock being in a qualifying Iowa corporation with an employee stock ownership plan of sufficient size. These are tests about a working life, not about a portfolio.
A sale of listed shares, an exchange-traded fund, a cryptocurrency holding, a second home or a rental property meets none of them. If that describes your sale — and for most people using a capital gains calculator it does — the deduction is not available and the flat 3.8% shown here is the right state figure. If it does not describe your sale, the figure here is an overstatement and the question is one for a preparer rather than a calculator.
What the move to a flat rate did to Iowa comparisons
Iowa arrived at 3.8% from a graduated schedule, and a good deal of the material written about Iowa income tax predates the change. Older comparisons place Iowa among the higher-taxing states on the strength of a top marginal rate that no longer exists.
On the current figure Iowa sits below Illinois at 4.95% and below Minnesota, and above Ohio at 2.75% and Indiana’s 2.95% state rate. For a capital gain that ordering is the whole story, because none of those states gives gains a preferential rate — the comparison is simply one flat proportion against another.
The practical caution is about sources rather than rates. An article about Iowa tax written three years ago is describing a different system, and the phase-down means even a recent figure needs its year attached to be worth anything.
What Iowa does not change
Your federal treatment is unaffected. The 0/15/20% long-term ladder, the 3.8% net investment income tax — a coincidence of numbers with the Iowa rate, and an entirely separate charge — the Section 121 home-sale exclusion and Section 1250 recapture all apply as normal.
The state figure stacks your gain on federal ordinary taxable income. Iowa computes its own taxable income with its own additions and subtractions, so treat the state number as close for a simple wage-and-sale year and approximate where the return carries state adjustments.
A worked Iowa example
Every figure below is computed by the same engine that powers the calculator above, at the moment this page was built — not typed in by hand. When the tax-year data is updated, this example updates with it.
A $180,000 gain on a $95,000 salary
A single filer in Iowa earning $95,000 sells long-held shares for a $180,000 gain. This is an ordinary investment sale, so no Iowa capital-gains deduction applies.
- Taxable income after deduction
- $258,900
- Taxable gain
- $180,000
- Tax owed without the sale
- $12,070
- Tax the sale added
- $29,850
- of which net investment income tax
- $2,850
- Total federal tax
- $41,920
- Iowa state tax
- $6,840
- Effective rate on the gain
- 16.58%
Iowa takes a flat 3.8% of the gain. Note that the state rate and the federal net investment income tax rate are both 3.8% — they are unrelated charges that happen to share a number, and a bill can carry both.
Caveats on this example (1)
- Net investment income was derived from capital gains and qualified dividends only. Interest, non-qualified dividends, rents, royalties and passive business income inside ordinaryIncome are also net investment income under IRC 1411(c) and are not counted here.
Show the working — 13 steps, each with its citation
- Net short-term capital gain or loss for the year$0
Assets held one year or less. Taxed at ordinary rates if a net gain.
- Net long-term capital gain or loss for the year$180,000
Assets held more than one year. Eligible for the 0/15/20% rates.
- Standard deduction-$16,100
Adjusted gross income of $275,000 less $16,100.
- Taxable income$258,900
The figure the rate tables and the capital gain ceilings are both measured against.
- Ordinary income taxed at 10%$1,240
$12,400 of taxable income between $0 and $12,400.
- Ordinary income taxed at 12%$4,560
$38,000 of taxable income between $12,400 and $50,400.
- Ordinary income taxed at 22%$6,270
$28,500 of taxable income between $50,400 and $78,900.
- Ordinary income stacked below the long-term gain$78,900
Long-term gain is taxed by reference to where it sits ON TOP of $78,900 of other taxable income, not from the bottom of the rate table.
- Long-term gain taxed at 15%$27,000
Gain between the $49,450 zero-rate ceiling and the $545,500 15% ceiling.
- Net investment income tax threshold$200,000
Modified AGI of $275,000 against the $200,000 threshold for a single filer. This threshold is statutory and is not adjusted for inflation.
- Net investment income tax at 3.8%$2,850
3.8% of $75,000, the lesser of net investment income ($180,000) and the amount by which modified AGI exceeds the threshold ($75,000). Here the binding figure is the excess of modified AGI over the threshold.
- Iowa income tax at 3.8%$6,840
Flat 3.8%, read from the Iowa Code 2026 edition, which states the tax is levied "at a rate of three and eight-tenths percent". Capital gains are ordinary income at that rate. Iowa does grant narrow capital-gain deductions under section 422.7 — for retired farmers selling farm property and for stock in a qualifying employee-owned Iowa company — but none reaches an ordinary sale of listed securities or a second home, so none is modelled here.
- Total tax$48,760
$48,760 on $275,000 of total income, an effective rate of 17.73%.
What this calculator does not cover for Iowa
The Iowa figure stacks your gain on your federal ordinary taxable income. Iowa computes its own taxable income with its own additions and subtractions, which are not modelled here — so treat the state number as a close approximation for a straightforward wage-and-sale situation, and as a rough one if your return carries significant state adjustments.
Full-year residency is assumed throughout. Part-year residents, non-residents, and gains sourced to property in another state all turn on rules this calculator does not model. The complete list of what is in and out of scope is on the methodology page.
Other states
- IllinoisFlat 4.95% on everything. No preferential rate, no exclusion.
- OhioA single 2.75% rate from 2026, above an indexed floor.
- ColoradoFlat 4.40%. The old capital gain subtraction appears to be gone.
See the full 2026 capital gains guide for the federal rules that apply wherever you live — the rate ladder, the net investment income tax, the home-sale exclusion and depreciation recapture — plus every state we currently cover.