Long-term capital gains: what a gain costs at your income
Enter ordinary taxable income and a long-term gain to see how much lands in the 0%, 15% and 20% bands, and what the 3.8% surcharge adds.
The 2026 ceilings on taxable income. A gain is not taxed at one rate: it stacks on top of your ordinary income, so the room left under the 0% ceiling is what decides the split.
Ordinary taxable income is your income after deductions, excluding the gain — that is the figure the bands are measured against. State tax, the alternative minimum tax, the qualified business income deduction and the Schedule D netting order are outside this calculation.
Single filer, tax year 2026, a gain held more than one year. Nothing changes here except the ordinary income on the left — which is the whole point of the table.
| Ordinary taxable income | Taxed at 0% | at 15% | at 20% | Federal tax on the gain |
|---|---|---|---|---|
| $0 | $49,450 | $550 | $0 | $82.50 |
| $25,000 | $24,450 | $25,550 | $0 | $3,832.50 |
| $49,450 | $0 | $50,000 | $0 | $7,500.00 |
| $520,000 | $0 | $25,500 | $24,500 | $8,725.00 |
| $545,500 | $0 | $0 | $50,000 | $10,000.00 |
At $49,450 of ordinary income the 0% band is exactly used up, and the whole gain pays 15%. Somewhere above $495,500 the gain starts to reach the 20% band — at $520,000 of ordinary income, $25,500 of it is still at 15% and the other $24,500 pays 20%. Once ordinary income reaches $545,500 the 15% band is full too, and the entire gain pays 20%: $10,000, whatever the ordinary income above that.
A long-term capital gain does not have a rate. It has a band, and where the band falls depends on a number you did not enter on the sale: the rest of your taxable income.
The tool above does one thing — it stacks the gain on top of your ordinary income and reports how much of it lands in each of the three federal bands. Everything on this page is about reading that output correctly.
The arithmetic the bands describe
The ceilings are on taxable income, not on the gain, and the statute works the two lower bands out of your ordinary income. In practice:
- Room at 0% is the 0% ceiling minus your ordinary taxable income — the gain fills that room first.
- Room at 15% runs from the top of the 0% band to the 15% ceiling. If your ordinary income already sits above the 0% ceiling, the whole of that band is available to the gain.
- The rest pays 20%.
For tax year 2026 the ceilings are $49,450 and $545,500 for a single filer, $98,900 and $613,700 for a married couple filing jointly, $49,450 and $306,850 for married filing separately, and $66,200 and $579,600 for a head of household.
Two single filers with the same $30,000 gain are the cleanest illustration, and they are in the guide this page supports. The first has $30,000 of ordinary taxable income, so $19,450 of the gain sits in the 0% band and $10,550 pays 15% — $1,582.50. The second has $60,000 of ordinary income, the 0% band is already full, and the same gain costs $4,500. Same sale, same year, same filing status.
What the tool will not tell you
- It is not your return. The bands interact with the alternative minimum tax, the qualified business income deduction and the Schedule D netting order, none of which are modelled.
- Short-term gains are not in here. A gain on an asset held one year or less is ordinary income, taxed at the graduated rates — the 0% band does nothing for it.
- State tax is separate, and in most states with an income tax the gain is taxed as ordinary income.
- The 3.8% surcharge needs your modified AGI, which is not the same figure as taxable income. Leave the field blank if you do not know it; the federal band arithmetic still works.
Where the numbers come from
The ceilings are restated every year for inflation, and the authority is the revenue procedure the IRS publishes each autumn for the following year — not the plain-language summary page for the topic, which lags. The 2026 amounts used here come from Revenue Procedure 2025-32, and the figures were last checked against it on 11 October 2026.
The rest of the rule — the holding period, the $3,000 loss door, the wash sale, the step-up in basis at death and the home-sale exclusion — is in Capital gains: what sets your rate, and what cancels your loss. Read that before using this page for anything beyond the arithmetic.
If you are weighing a sale against a retirement contribution instead, the marginal-rate question is the same one in Roth or traditional.
Frequently asked questions
- Why is only part of my gain taxed at 0%?
- Because the 0% band is a ceiling on taxable income, and the gain sits on top of your ordinary income. The room available at 0% is the 0% ceiling minus your ordinary taxable income, and the gain fills that room first. Anything left over moves up to 15%, and then to 20%.
- Does the calculator include state tax?
- No. It is federal only, and state treatment varies widely — most states with an income tax tax capital gains as ordinary income, some give a preferential rate, and a handful have no income tax at all. The figures here are the federal bands for tax year 2026.
- What is the 3.8% figure at the bottom?
- The net investment income tax. It is a separate tax on the lesser of your net investment income and the amount by which your modified adjusted gross income exceeds the threshold — $200,000 single or head of household, $250,000 married filing jointly, $125,000 married filing separately. It phases in rather than switching on, which is why the field is optional: without your modified AGI there is nothing to compute it against.
- I have a loss, not a gain. Does this page help?
- Not directly — the bands apply to gains. Losses first offset gains, and only $3,000 of an excess loss can reduce ordinary income in a year ($1,500 if married filing separately); the rest carries forward. See the guide linked below for the wash-sale rule, which is what usually voids the tidy version of the trade.
Sources
- Internal Revenue Service, Revenue Procedure 2025-32 (tax year 2026 inflation adjustments; the maximum zero rate amount and the maximum 15 percent rate amount are set by section 1(h) as modified by section 1(j)(5)(B) and are listed at section 4.03) (irs.gov/pub/irs-drop/rp-25-32.pdf)
- 26 U.S.C. section 1(h)(1) (the rate structure itself, in which the 0 percent and 15 percent bands are measured against taxable income reduced by the adjusted net capital gain) (govinfo.gov, United States Code 2023 Edition, Title 26, Chapter 1, Subchapter A, Part I, Sec. 1)
- 26 U.S.C. section 1411 (net investment income tax) and Internal Revenue Service Topic no. 559 (govinfo.gov, United States Code 2023 Edition, Title 26; irs.gov/taxtopics/tc559)
- Internal Revenue Service, Topic no. 409, Capital gains and losses (the holding period and the treatment of short-term gains as ordinary income)