US Capital Gains Tax: Rates, Rules & Strategies (2025)

Accounting › Country Tax Guides › US Tax

US capital gains tax rewards long-term investing with sharply lower rates than ordinary income. This guide explains the difference between short- and long-term gains, the 2025 long-term rates of 0%, 15% and 20%, the income thresholds, the 3.8% Net Investment Income Tax, and strategies like tax-loss harvesting to manage your capital gains tax.

What is capital gains tax?

Capital gains tax applies to the profit when you sell a capital asset — stocks, bonds, real estate, or other investments — for more than you paid. The gain is the sale price minus your cost basis (what you paid plus certain costs). You only owe the tax when you ‘realize’ the gain by selling; unrealized gains on assets you still hold aren’t taxed.

The key distinction is how long you held the asset. Hold it more than a year and you get preferential long-term capital gains rates; sell within a year and the gain is short-term, taxed at your ordinary income rate. This holding-period rule makes patience genuinely valuable, as the rate difference between short- and long-term treatment can be substantial.

What are the long-term capital gains rates for 2025?

For 2025, long-term capital gains are taxed at 0%, 15% or 20% depending on your taxable income. The 0% rate applies up to $48,350 of taxable income for single filers and $96,700 for married couples filing jointly. The 15% rate covers most middle- and upper-middle-income taxpayers, and the 20% rate applies to high earners above roughly $533,400 (single) — confirm current thresholds on IRS.gov.

These rates are markedly lower than the ordinary income brackets, which top out at 37%. The preferential treatment is designed to encourage long-term investment. Notably, the rate depends on your total taxable income, so part of a gain can be taxed at 0% and the rest at 15% if it straddles a threshold — making capital gains planning around your income level worthwhile.

How are short-term gains taxed?

Short-term capital gains — on assets held one year or less — get no preferential treatment. They’re taxed as ordinary income at your regular bracket, which can be as high as 37%. So a quick flip of a stock or property is taxed far more heavily than the same gain on an asset held just over a year, which would qualify for long-term rates.

This is why the one-year holding period is such an important line. An investor who sells at 11 months pays ordinary rates; waiting past 12 months can cut the rate dramatically. For active traders, most gains are short-term and taxed as income, while long-term investors benefit from the lower capital gains rates — a key reason buy-and-hold investing is tax-efficient.

What is the Net Investment Income Tax?

High earners may owe an additional 3.8% Net Investment Income Tax (NIIT) on investment income, including capital gains, dividends and interest, when their income exceeds certain thresholds. This applies on top of the regular capital gains rate, so a top-rate investor could face a combined 23.8% on long-term gains (20% plus 3.8% NIIT).

The NIIT was introduced to help fund healthcare and targets investment income of higher-income taxpayers. It applies to both short- and long-term gains and to other investment income above the threshold. For high earners, factoring in the NIIT is essential when estimating the true tax on investment gains, as it meaningfully raises the effective rate on their capital gains and dividends.

What is tax-loss harvesting?

Tax-loss harvesting means selling investments that have lost value to realize capital losses, which offset your capital gains and reduce the tax owed. If your losses exceed your gains, you can use up to $3,000 of net losses to offset ordinary income each year, and carry forward any remaining losses to future years. It’s a powerful way to manage capital gains tax.

The strategy lets investors turn portfolio losses into tax savings, offsetting gains from winners with losses from losers. Care is needed to avoid the ‘wash sale’ rule, which disallows the loss if you buy back the same or a substantially identical security within 30 days. Done correctly, tax-loss harvesting is a cornerstone of tax-efficient investing, especially in volatile markets.

How are capital gains reported?

Capital gains and losses are reported on Form 8949 and summarized on Schedule D, attached to your Form 1040. Brokerages issue Form 1099-B showing your sales and often your cost basis, which feeds these forms. Mutual funds and ETFs may also distribute capital gains, reported on 1099-DIV, even if you didn’t sell — which can create a tax bill from funds you still hold.

Accurate cost-basis tracking is essential to calculating the right gain, especially for assets bought over time or inherited. The brokerage usually tracks basis for recent purchases, but older holdings may require your own records. Reporting capital gains correctly, with the proper basis and holding period, ensures you pay the right tax and claim the preferential long-term rates you’re entitled to.

A practical example: long-term vs short-term

Suppose an investor in the 24% bracket has a $10,000 gain. If short-term, it’s taxed at 24% — $2,400. If long-term, it’s likely taxed at 15% — $1,500. Simply by holding the asset past one year, the investor saves $900 on the same $10,000 gain, a 37.5% reduction in the tax owed on that profit.

For a lower-income investor whose taxable income falls under the 0% threshold, that same long-term gain might be taxed at 0% — entirely tax-free. The example shows why holding period and income level are the two levers that drive capital gains tax, and why timing sales and managing taxable income are central to tax-efficient investing.

How are home sales taxed?

Selling your primary residence gets a valuable break: the home-sale exclusion lets you exclude up to $250,000 of gain (single) or $500,000 (married filing jointly) from capital gains tax, provided you owned and lived in the home for at least two of the last five years. Gains above the exclusion are taxed at long-term capital gains rates.

This exclusion means most homeowners pay no tax on the sale of their main home. It can be used repeatedly, though generally not more than once every two years. Investment and second properties don’t qualify and are fully taxable, sometimes with additional considerations like depreciation recapture on rentals. Understanding the home-sale exclusion is important for anyone selling a residence with significant appreciation.

What is a step-up in basis?

When assets pass to heirs at death, they generally receive a ‘step-up in basis’ to the fair market value at the date of death. This means the heirs’ cost basis becomes the value when inherited, erasing the capital gains tax on appreciation during the deceased’s lifetime. Heirs who sell soon after inheriting may owe little or no capital gains tax.

The step-up is a major feature of US tax and estate planning, as it can eliminate decades of unrealized gains. It’s one reason some investors hold appreciated assets until death rather than selling. For heirs, understanding the stepped-up basis is essential to calculating any gain on inherited assets, since their basis reflects the value at inheritance, not what the deceased originally paid.

How does capital gains tax apply to real estate investing?

Investment real estate has its own capital gains considerations. Gains on sold rental or investment property are taxed at long-term rates if held over a year, but depreciation claimed over the years is ‘recaptured’ and taxed, often at a higher rate. Investors can defer gains through a 1031 like-kind exchange, rolling proceeds into another investment property.

The 1031 exchange is a powerful deferral tool, letting real estate investors postpone capital gains tax indefinitely by reinvesting in qualifying property. Combined with depreciation deductions during ownership and a potential step-up in basis at death, real estate offers distinctive tax advantages. Understanding depreciation recapture and 1031 exchanges is essential for property investors managing their capital gains exposure.

Why capital gains planning matters

Capital gains tax is one of the most controllable taxes, because you choose when to realize gains by selling. This control enables powerful planning: timing sales for low-income years to hit the 0% or 15% rate, harvesting losses to offset gains, holding past one year for long-term treatment, and using tax-advantaged accounts to shelter gains entirely.

For investors, mastering these levers can dramatically reduce the lifetime tax on investment returns. The difference between careless and tax-aware selling can amount to thousands of dollars over time. Capital gains planning sits at the heart of tax-efficient investing, and understanding the rates, thresholds and strategies covered here empowers investors to keep more of what their investments earn.

Common capital gains mistakes to avoid

Frequent errors include selling just before the one-year mark and paying ordinary rates, triggering wash sales that disallow harvested losses, forgetting that fund distributions create taxable gains, miscalculating cost basis (especially with reinvested dividends), and overlooking the NIIT. Each can needlessly increase the tax on investment profits.

Avoiding them means tracking holding periods, waiting 31 days before repurchasing harvested positions, keeping accurate basis records, and factoring in the NIIT for high incomes. Because capital gains tax is so controllable, these mistakes are largely preventable with awareness and planning. Tax-aware selling and good records turn capital gains from an afterthought into a managed, optimized part of investing.

How does state tax affect capital gains?

Most states tax capital gains as ordinary income, with no preferential rate like the federal 0/15/20% structure. So a gain taxed at 15% federally might face an additional state tax of several percent, raising the combined rate. States with no income tax impose no state capital gains tax at all, while high-tax states add a significant layer.

This makes your state of residence a real factor in the total tax on investment gains. High earners in high-tax states can face combined federal-plus-state-plus-NIIT rates well above the headline federal figure. For those with flexibility, the state-tax treatment of gains is one consideration in residency decisions, and it’s always part of estimating the true after-tax return on a sale.

Frequently Asked Questions