If you sell an investment for more than you paid for it, the profit is a capital gain — and the IRS generally taxes it. But capital gains tax is not one flat rate. It depends on how long you held the asset, your taxable income, and what type of asset you sold. This guide explains the rules in plain terms and shows the levers you can pull to keep more of your gain.
What Counts as a Capital Gain (and a Capital Loss)
A capital gain is the difference between your basis in an asset and the amount you receive when you sell it. Your basis is usually what you paid, plus certain costs like commissions, and minus any depreciation you claimed. If you sell for less than your basis, you have a capital loss.
Capital assets include most things you own for investment or personal use:
- Stocks, bonds, mutual funds, and exchange-traded funds held in a taxable brokerage account
- Real estate that is not your primary residence, and sometimes your primary residence above the exclusion amount
- Cryptocurrency and other digital assets, which the IRS treats as property
- Collectibles such as art, coins, and antiques
- Business assets and partnership or S corporation interests
Your home is a special case. Under Section 121, you can exclude up to $250,000 of gain if you are single, or $500,000 if married filing jointly, provided you owned and lived in the home as your main residence for at least two of the five years before the sale.
Short-Term vs. Long-Term Capital Gains Tax Rates
The holding period is the single biggest factor in your tax bill. Hold an asset for one year or less and the gain is short-term, taxed at your ordinary income rates — 10% to 37% for 2025, depending on your bracket. Hold it for more than one year and the gain is long-term, taxed at preferential rates of 0%, 15%, or 20%.
For 2025, the long-term brackets for most filers are roughly:
- 0% — taxable income up to $48,350 single, $96,700 married filing jointly
- 15% — income up to $533,400 single, $600,050 married filing jointly
- 20% — income above those thresholds
These thresholds are adjusted annually for inflation, and the 0% bracket is often overlooked. A retiree living on modest income, for example, may owe nothing on a long-term gain.
Two surtaxes can raise the effective rate. The net investment income tax adds 3.8% on the lesser of your net investment income or the amount by which modified adjusted gross income exceeds $200,000 single or $250,000 married filing jointly. And a portion of your gain can push other income into a higher bracket, which is why the marginal rate on a gain can exceed the headline rate.
Special Rates for Collectibles, Real Estate, and Qualified Small Business Stock
Not every long-term gain gets the 0/15/20 treatment. Collectibles — art, antiques, metals, gems, and certain coins — are taxed at a maximum 28% rate. Unrecaptured Section 1250 gain on depreciated real estate is taxed at up to 25%. Gains on qualified small business stock under Section 1202 may be partially or fully excluded if you meet the five-year holding and other requirements.
Short-term gains from assets held in a tax-deferred account like a 401(k) or traditional IRA are not taxed when you sell; you pay ordinary income tax when you withdraw. Roth accounts generally allow tax-free qualified withdrawals.
How to Calculate Your Capital Gains Tax
The mechanics are straightforward once you have the pieces:
- Determine your proceeds — the sale price minus commissions and fees.
- Determine your basis — purchase price plus costs, adjusted for reinvested dividends, splits, or depreciation.
- Subtract basis from proceeds. A positive number is a gain; a negative number is a loss.
- Net your gains and losses. Short-term losses first offset short-term gains, and long-term losses offset long-term gains. Excess losses can offset up to $3,000 of ordinary income per year, with the rest carried forward.
- Apply the correct rate to the remaining net gain based on holding period and your taxable income.
Brokerages report proceeds and basis on Form 1099-B, and you report the results on Schedule D and Form 8949. Keep your own records anyway — basis reporting is not always complete, especially for older positions or assets you transferred between brokers.
Strategies to Reduce Capital Gains Tax
There is no single trick, but several legitimate moves can lower the bill:
- Hold past one year. Crossing the 12-month mark can cut your rate from 37% to 20% or lower.
- Harvest losses. Sell underperforming positions to offset gains. Watch the wash-sale rule, which disallows the loss if you buy a substantially identical security within 30 days before or after the sale.
- Use the 0% bracket. If your taxable income is low, realize long-term gains up to the top of the 0% bracket.
- Donate appreciated shares. Giving stock held more than a year to a qualified charity avoids the capital gain and may produce a charitable deduction for the fair market value.
- Contribute to tax-advantaged accounts. Max out a 401(k), traditional IRA, or health savings account to reduce taxable income and potentially keep gains in a lower bracket.
- Time the sale. Spreading gains across tax years can keep you under a bracket threshold or the net investment income tax trigger.
Each strategy has eligibility rules. A tax professional can model the numbers before you execute.
What to Remember
Capital gains tax rewards patience: holding an asset for more than a year moves the gain from ordinary rates to 0%, 15%, or 20%. Know your basis, track your holding period, and use losses, charitable giving, and tax-advantaged accounts deliberately. The rules are detailed, but the core idea is simple — the longer you hold and the more you plan, the less you typically owe.
