Capital gains tax has a reputation for being complicated, but almost everything about it comes down to a single question: did you hold the asset for more than a year? The answer splits your gain into one of two worlds with very different rates, and understanding that split is most of what you need to plan a sale well.
Here is the part that surprises people most. The federal long-term capital gains rate can be 0 percent, and not just for the wealthy. Whether a gain is taxed at 0, 15, or 20 percent depends on your total taxable income, and a household whose taxable income sits inside the lowest band pays nothing federally on its long-term gains that year.
The rates and thresholds below are for the 2026 tax year. The capital gains tax calculator always applies the current year’s figures, so a reader in a later year can pull the live numbers there.
How does capital gains tax work?
A capital gain is simply your sale price minus your cost basis, what you paid. When you sell an asset for more than you paid, that profit is a capital gain, and how it is taxed depends on the holding period.
The IRS draws the line at one year. Hold an asset more than a year and the gain is long-term, eligible for the preferential 0, 15, or 20 percent rates. Hold it a year or less and it is short-term, taxed at your ordinary income rate, the same brackets that apply to your wages. That difference can easily double the tax on the same dollar of profit.
Why does holding for a year matter so much?
Because the ordinary rates climb to 37 percent while the long-term rates stop at 20 percent. Take a $15,000 gain for a single filer with $80,000 of other taxable income in 2026:
- Held over a year (long-term): the $80,000 sits inside the 15 percent long-term band, so the whole gain is taxed at 15 percent, which is $2,250.
- Held a year or less (short-term): the gain stacks on the $80,000 and runs through the 22 percent ordinary bracket, costing about $3,300.
Same profit, roughly $1,050 more tax, decided entirely by the calendar. If you are close to the one-year mark, waiting can be one of the highest-return decisions available to you. Run your own numbers in the capital gains tax calculator to see the gap for your situation.
How can my capital gains rate be 0 percent?
This is the most underused rule in investing. The long-term rate is based on your total taxable income, and the lowest band is taxed at 0 percent.
| Filing status | 0% up to | 15% up to | 20% above |
|---|---|---|---|
| Single | $49,450 | $545,500 | $545,500 |
| Married filing jointly | $98,900 | $613,700 | $613,700 |
| Head of household | $66,200 | $579,600 | $579,600 |
The key is that long-term gains stack on top of your ordinary income, filling the bands from the bottom. So if a single filer has $30,000 of ordinary taxable income and a $15,000 long-term gain, the first $19,450 of the gain fits inside the 0 percent band (up to $49,450) and is untaxed, and only the remaining part is taxed at 15 percent. Part of one gain at 0 percent, part at 15 percent, is completely normal.
A planning lever for low-income years
In a year when your income dips, a sabbatical, early retirement before pensions start, a gap between jobs, you may be able to realize long-term gains in the 0 percent band on purpose. This is sometimes called tax-gain harvesting, and it can reset your cost basis higher at no federal tax cost.
Who pays the extra 3.8 percent?
Higher earners owe the Net Investment Income Tax on top of the regular capital gains tax. The IRS describes it as 3.8 percent on the lesser of your net investment income or the amount your modified adjusted gross income exceeds the threshold, which is $200,000 for single filers and $250,000 for married filing jointly.
Because those thresholds were set in 2013 and have never been indexed for inflation, more households cross them every year through ordinary income growth alone. A large gain can push you over the line, so on a big sale the real top federal rate is not 20 percent but 23.8 percent.
What about state capital gains tax?
The 0, 15, and 20 percent rates are federal only. Most states tax capital gains as ordinary income at their regular rate, with no long-term discount, so a state like California can add over 13 percent at the top. A few states have separate capital gains rules. To estimate the full bill, add your state’s ordinary income rate to the federal result; the state paycheck calculators show those state rates, and short-term gains in particular are taxed just like the wage income there.
The bottom line
Federal capital gains tax is mostly one decision: hold more than a year for the 0, 15, or 20 percent long-term rates, or pay your ordinary rate on a short-term gain. The long-term rate depends on your total taxable income, the gain stacks on top of it, and high earners add 3.8 percent for the NIIT. Before you sell anything, run the sale through the capital gains tax calculator with your real income and holding period. If you are close to the one-year mark, that single check tells you what waiting is worth.