Capital gains in plain English
A capital gain generally occurs when a capital asset is sold or otherwise disposed of for more than its adjusted tax basis. A capital loss generally occurs when the amount realized is lower than adjusted basis.
Stocks, bonds, funds, real estate, and many items held for personal or investment purposes are capital assets. Business inventory and certain other property follow different rules.
An increase on a statement is an unrealized gain while the asset is still owned. A sale or other taxable disposition usually realizes the result and creates a reporting event.
Amount realized and adjusted basis
The basic calculation is:
capital gain or loss = amount realized − adjusted basis
Amount realized generally begins with cash and the fair value of property received, adjusted for selling costs. Basis often begins with purchase cost, including applicable acquisition expenses.
Basis can change. Reinvested fund distributions, stock splits, return-of-capital distributions, improvements to real estate, depreciation, gifts, inheritance, wash sales, and corporate actions can all affect it.
A broker's displayed “cost” is useful but not always the complete tax basis. Keep confirmations, closing statements, reinvestment records, and adjustment notices.
A simple example
An investor buys shares for $8,000 and pays $20 of acquisition costs, creating an initial basis of $8,020. The shares are later sold for $10,500 with $25 of selling costs, producing $10,475 of amount realized.
The capital gain is $2,455. Tax is not calculated on the full $10,475 of proceeds.
If basis had been adjusted by a return-of-capital distribution or wash-sale rule, the result would differ. The arithmetic is simple only after the inputs are correct.
Short-term versus long-term
The holding period determines the category. A gain or loss is generally long-term when the asset was held for more than one year and short-term when held for one year or less.
Counting can have special rules. The holding period generally starts the day after acquisition and includes the disposition date, but gifts, inherited property, options, short sales, and other transactions can differ.
Short-term net gains are generally taxed at ordinary income rates. Net long-term gains may qualify for lower federal rates, although exceptions apply.
Netting gains and losses
Federal tax does not simply apply a rate to every sale independently. Transactions are separated into short-term and long-term groups.
Within each group, gains and losses offset. The net short-term and net long-term results are then combined under the ordering rules. A loss in one category can offset a gain in the other.
If total capital losses exceed total capital gains, an individual may generally deduct up to $3,000 of net capital loss against other income, or $1,500 when married filing separately. Unused loss generally carries forward to later years.
Carryforwards retain their character and should be documented from the prior return.
Personal-use property is different
A gain on the sale of personal-use property can be taxable, but a loss on personal-use property generally is not deductible.
Selling a used car or furniture for less than its cost usually does not create a deductible capital loss. Investment-property losses may be deductible subject to the capital-loss rules.
The sale of a main home has a separate exclusion framework when ownership, use, and other requirements are met. It should not be analyzed as an ordinary stock sale.
Mutual funds and reinvested distributions
A fund can distribute capital gains even when the shareholder did not sell fund shares. The fund reports the distribution, and it can be taxable in a nonretirement account.
When a distribution is automatically reinvested, it generally buys additional shares and adds basis. Omitting those reinvested amounts can cause the same dollars to be taxed again when the shares are sold.
Different lots may have different acquisition dates and bases. Use an eligible basis method consistently and preserve any identification instructions.
Gifts and inherited assets
Property received as a gift can carry the donor's basis and holding information, with special dual-basis rules when value has declined. The recipient should obtain the donor's records before a later sale.
Inherited-property basis is generally connected to fair market value at the decedent's death or an applicable alternate valuation, but exceptions and community-property rules can matter.
Do not assume that receiving an asset for no cash means its basis is zero.
Wash sales
The wash-sale rule can disallow a loss when substantially identical stock or securities are acquired within the period beginning 30 days before and ending 30 days after the loss sale.
The disallowed loss is generally added to the basis of replacement shares and the holding period carries over. Purchases in another brokerage account or an IRA can complicate the result, and broker reporting may not capture every cross-account transaction.
Harvesting a loss without reviewing planned purchases, automatic reinvestments, and household accounts can create an unintended wash sale.
Reporting a sale
Broker transactions are commonly reported on Form 1099-B. The taxpayer generally reports details on Form 8949 and summarizes them on Schedule D, subject to exceptions in the form instructions.
Compare proceeds, basis, holding period, and adjustment codes with personal records. A blank basis on Form 1099-B does not eliminate the need to determine basis.
Report taxable sales even when no form arrived. Retain records supporting acquisition, improvements, adjustments, and disposition.
Special-rate property
Not every long-term gain uses only the familiar general rate structure. Collectibles gain and certain qualified small-business stock gain can face a maximum 28% rate. Unrecaptured Section 1250 gain related to depreciated real property can face a maximum 25% rate.
Depreciation recapture, business-property rules, installment sales, options, cryptocurrency transactions, and partnership interests may require additional forms and calculations.
The label “long-term” is necessary information, not a complete tax answer.
Capital gains inside retirement accounts
Buying and selling investments inside a traditional IRA, Roth IRA, or qualified workplace plan generally does not create current Schedule D capital gains for the account owner.
Distributions follow the account's tax rules instead. A taxable traditional-account distribution is generally ordinary income, while a qualified Roth distribution can be tax-free.
Holding a security inside an account wrapper changes the tax mechanics even when the investment gain is economically similar.
Estimated payments and withholding
A large realized gain can increase tax beyond wage withholding. Federal estimated-tax rules and underpayment safe harbors determine whether an additional payment is needed during the year.
State tax may also apply, and states do not necessarily use federal rates or exclusions. Estimate before spending all sale proceeds.
Taxes are based on the full return—including losses, deductions, income, filing status, and special taxes—not merely the broker's gain estimate.
A capital-gain recordkeeping checklist
Before filing:
- match every sale with acquisition records;
- verify adjusted basis and amount realized;
- confirm holding period and lot selection;
- review wash sales across relevant accounts;
- carry forward prior capital losses correctly;
- identify personal-use and special-rate property; and
- reconcile Forms 8949 and Schedule D with information returns.
Capital-gain reporting is accurate when the history of the asset is accurate. The sale price is only one part of that history.