Unrealized capital gains are increases in the value of assets you still own, and under current federal law they are not taxed. The IRS only reaches a capital gain after you sell, exchange, or otherwise dispose of the asset. That realization requirement puts the timing of the tax largely in your hands, because in most cases you decide when the sale happens.1Office of the Law Revision Counsel. 26 USC 1001 – Determination of Amount of and Recognition of Gain or Loss
What an Unrealized Gain Actually Is
An unrealized gain is the difference between what your asset is worth today and what you paid for it. Buy 100 shares at $50 and watch the price climb to $80, and you’re sitting on a $3,000 paper profit. Nothing has changed hands. The market could drop tomorrow, and the IRS has no claim on that appreciation.
The anchor for the calculation is your cost basis: generally the purchase price plus the costs tied to acquiring the asset. For stocks and bonds, that includes commissions and transfer fees. For real estate, it includes closing costs, recording fees, and improvements with a useful life beyond one year. Basis also moves down over time if you claim depreciation or receive nontaxable distributions.2Internal Revenue Service. Publication 551 (12/2025), Basis of Assets
Keeping that number accurate matters more than many investors realize. Stock splits, reinvested dividends, and property improvements all adjust it. Get it wrong and you’ll either overpay when you sell or underreport your gain and face penalties. Brokerages report basis to the IRS for shares bought after certain coverage dates, but the burden of proving the right figure still falls on you.3Internal Revenue Service. Instructions for Schedule D (Form 1040) (2025)
When the Gain Becomes Taxable
An unrealized gain turns into a realized gain the moment you sell, exchange, or otherwise dispose of the asset. That transaction fixes a sale price and a date, and the IRS uses both to calculate the tax. Before that event, the gain fluctuates with the market and carries no tax consequence.
The underlying principle is the realization doctrine. Income generally isn’t taxable until a completed transaction has fixed it. Since you can’t spend an unrealized gain without selling first, it isn’t treated as income. Wages and interest work differently and are taxed as you receive them.
One meaningful exception to immediate recognition on a sale is the like-kind exchange. Under Section 1031, you can swap one piece of investment or business real estate for another of like kind and defer the tax on your gain. Since 2018, this treatment applies only to real property; stocks, bonds, equipment, and other personal property are excluded.4Office of the Law Revision Counsel. 26 US Code 1031 – Exchange of Real Property Held for Productive Use in a Trade or Business or for Investment Real property held primarily for resale doesn’t qualify either.5Internal Revenue Service. Like-Kind Exchanges – Real Estate Tax Tips The gain isn’t forgiven; it’s rolled into the basis of the replacement property, so the tax eventually comes due when you sell for cash, unless the step-up at death intervenes first.
What You’ll Owe Once You Sell
Once a sale realizes the gain, the rate depends on how long you held the asset. The dividing line is one year.
Short-Term Gains
Assets held for a year or less are taxed at your ordinary income rate, which runs as high as 37% federally for top earners. There’s no preferential treatment; the gain stacks on top of your other income.6Internal Revenue Service. Topic No. 409, Capital Gains and Losses
Long-Term Gains
Hold for more than a year and the gain qualifies for the long-term rates of 0%, 15%, or 20%, with the rate set by your taxable income and filing status. For 2026, the brackets are:7Internal Revenue Service. Revenue Procedure 2025-32
- 0% up to $49,450 for single filers, $98,900 for married filing jointly, or $66,200 for head of household.
- 15% above those amounts and up to $545,500 for single filers, $613,700 for married filing jointly, or $579,600 for head of household.
- 20% above the 15% ceiling.
These thresholds are adjusted annually for inflation, so they rise a bit each year.
The Net Investment Income Tax
High earners owe an additional 3.8% net investment income tax on capital gains, dividends, and other investment income. The NIIT applies once modified adjusted gross income passes $200,000 if you’re single, $250,000 if married filing jointly, or $125,000 if married filing separately.8Internal Revenue Service. Topic No. 559, Net Investment Income Tax Those thresholds are set by statute and don’t adjust for inflation, so more filers cross them each year.
Collectibles
Gains on collectibles like coins, fine art, and precious metals face a maximum federal rate of 28%, even on long-term holdings. That’s noticeably higher than the 20% cap on most other long-term gains.6Internal Revenue Service. Topic No. 409, Capital Gains and Losses
Where Unrealized Gains Commonly Build Up
Stocks, ETFs, and Mutual Funds
Publicly traded securities are the most familiar source of paper gains, with prices moving every trading day. One wrinkle catches people off guard: mutual funds are required to distribute realized capital gains to shareholders each year. You owe tax on those distributions even if you reinvested everything and never sold a share yourself. The reinvested amount gets added to your basis, which reduces the gain when you eventually sell the fund.
Real Estate
Property held for years often accumulates sizable unrealized gains, especially a primary residence. On the sale of a main home, you can exclude up to $250,000 of gain from income, or $500,000 if married filing jointly, as long as you owned and lived in the home for at least two of the five years before the sale.9Office of the Law Revision Counsel. 26 USC 121 – Exclusion of Gain From Sale of Principal Residence Investment properties don’t get this exclusion, though they may qualify for a 1031 exchange.
Cryptocurrency and Digital Assets
The IRS treats digital assets as property, not currency. Unrealized gains on crypto aren’t taxed, and the usual short- and long-term holding period rules apply when you sell, trade, or otherwise dispose of the asset.10Internal Revenue Service. Digital Assets Using crypto to buy goods or services also triggers realization, which surprises people who think of it as spending rather than selling.
Collectibles
Rare coins, fine art, antiques, and precious metals all generate paper gains as they appreciate. Keep the 28% maximum rate in mind when planning a sale, and keep your own purchase records, since collectibles don’t come with the automatic basis reporting that brokerages provide for stocks.
The Narrow Exceptions Where Unrealized Gains Are Taxed
A few carve-outs do reach appreciation before a sale. Securities dealers must “mark to market” their inventory at year-end under Section 475, recognizing gain or loss as if every security had been sold on the last business day of the year. The resulting gain or loss is ordinary, not capital.11Office of the Law Revision Counsel. 26 US Code 475 – Mark to Market Accounting Method for Dealers in Securities Certain traders who aren’t dealers can also elect this treatment, with trade-offs beyond the scope of this piece.
Recurring proposals in Congress would tax unrealized gains more broadly, particularly for ultra-high-net-worth individuals. As of early 2026, no such federal law has been enacted, and the realization requirement remains intact for the vast majority of taxpayers.
Managing a Gain Before You Sell
Tax-Loss Harvesting
If some holdings are below your cost, you can sell them to realize losses that offset realized gains dollar for dollar. Any leftover loss can offset up to $3,000 of ordinary income per year, or $1,500 if married filing separately, with unused amounts carrying forward indefinitely.12Office of the Law Revision Counsel. 26 USC 1211 – Limitation on Capital Losses Watch the wash sale rule: buy the same or a substantially identical security within 30 days before or after selling at a loss, and the IRS disallows the loss for that year. The disallowed amount gets added to the basis of the replacement shares, so it isn’t permanently lost, but the immediate benefit is gone.
Donating Appreciated Assets
Giving appreciated stock or other capital gain property directly to a qualified charity lets you skip the capital gains tax while deducting the full fair market value. The deduction for appreciated capital gain property donated to a public charity is capped at 30% of your adjusted gross income for the year, with unused amounts carrying forward for up to five additional years.13Internal Revenue Service. Publication 526 (2025), Charitable Contributions It’s one of the few ways to eliminate a capital gains liability outright instead of merely deferring it.
Timing the Sale
Because you choose when to sell, you can push realizations into lower-income years. Retiring mid-year, taking a sabbatical, or bunching sales into a lean year can land long-term gains in the 0% bracket. The 2026 zero-rate threshold covers nearly $50,000 of taxable income for a single filer and close to $99,000 for a married couple filing jointly.7Internal Revenue Service. Revenue Procedure 2025-32
The Step-Up at Death
Holding an appreciated asset for life carries a powerful tax consequence. When you die, your heirs receive a stepped-up basis equal to the fair market value on the date of death. All the appreciation that accumulated during your lifetime is wiped from the tax ledger.14Office of the Law Revision Counsel. 26 USC 1014 – Basis of Property Acquired From a Decedent
Buy stock for $10,000 that’s worth $500,000 at your death, and your heirs’ basis becomes $500,000. If they sell right away, they owe no capital gains tax. Inherited property also automatically qualifies for long-term capital gain treatment, regardless of how quickly they sell. A 1031 exchange chain that ends at death can erase decades of deferred gains in a single stroke. Many states also layer their own income tax on realized gains, with rates ranging from 0% in states without an income tax to over 13% in the highest-tax states. Between federal, state, and the NIIT, the combined rate on a large realized gain can exceed 37%, which is why the step-up matters so much to long-term planning.