Short-Term vs. Long-Term Capital Gains: The Difference Is Enormous
The single most important factor in capital gains taxation is how long you held the asset before selling. Assets held for one year or less are subject to short-term capital gains tax, which is taxed at ordinary income rates — the same progressive brackets that apply to your wages, ranging from 10% to 37% in 2025. Assets held for more than one year qualify for long-term capital gains rates of 0%, 15%, or 20%, depending on your income level. For most middle-income earners, this distinction can save thousands of dollars in taxes on a single sale.
Consider a $30,000 gain on a stock position. If you sell after 10 months and your marginal federal rate is 22%, you'll owe $6,600 in federal tax. Wait two more months, and as a long-term gain with a 15% rate, you'd owe only $4,500 — a $2,100 difference just by holding longer. This is why investors are often advised to hold positions for at least 366 days before selling, especially near year-end when the decision can be made with just weeks of patience.
2025 Long-Term Capital Gains Tax Brackets
The IRS uses three long-term capital gains rates based on your total taxable income (including the gain itself). For 2025, single filers pay 0% on long-term gains if their total taxable income is $47,025 or below, 15% up to $518,900, and 20% above that threshold. Married filing jointly taxpayers have higher thresholds: 0% up to $94,050, 15% up to $583,750, and 20% above. Head of household filers fall between: 0% up to $63,000, 15% up to $551,350, and 20% above.
An important nuance: the capital gain is stacked on top of ordinary income when determining which bracket applies. If you have $80,000 in ordinary income and $50,000 in long-term gains as a single filer, your total income is $130,000 — well into the 15% bracket. The 0% rate only applies to the portion of gain that keeps your total income below the 0% threshold. This calculator accounts for this stacking effect to compute your marginal rate accurately.
The Net Investment Income Tax (NIIT)
High-income taxpayers face an additional 3.8% Net Investment Income Tax on capital gains and other investment income. This surtax applies to the lesser of your net investment income or the amount by which your modified adjusted gross income (MAGI) exceeds the threshold: $200,000 for single filers and $250,000 for married filing jointly. For a single filer earning $220,000 in wages plus $50,000 in capital gains, the NIIT applies to $70,000 ($220,000 + $50,000 = $270,000 MAGI minus $200,000 threshold). This effectively raises the top federal capital gains rate from 20% to 23.8%.
Strategies to Reduce Capital Gains Taxes
Tax-loss harvesting is one of the most powerful tools for managing capital gains. By deliberately selling underperforming investments at a loss, you generate capital losses that offset capital gains dollar-for-dollar. Up to $3,000 of excess losses can be deducted against ordinary income each year, with remaining losses carried forward indefinitely. Holding appreciated assets until death eliminates capital gains entirely through the step-up in basis — heirs inherit assets at their fair market value at the date of death. Donating appreciated assets directly to charity avoids capital gains while generating a deduction for the full market value.