You pay capital gains tax through your annual tax return, either by sending a check with Form 1040 or by having the IRS deduct it from a refund

Capital gains tax is not a separate bill that arrives in the mail. Instead, you report the gain (the profit from selling an investment) on your federal tax return, calculate what you owe based on your tax bracket, and then pay it along with any other income tax you owe. The IRS does not know you sold something until you tell them on your return.

Most people pay through one of two methods: they either send a check or money order with their return, or they authorize the IRS to take the payment from their refund. Some people make quarterly estimated tax payments throughout the year if they expect a large gain. The timing and method depend on when you sold the investment and when you file your return.

Key Takeaways

  • You report capital gains on Schedule D (Form 1040) when you file your federal tax return, not on a separate form sent to the IRS.
  • The tax is due on April 15 of the year after you sold the investment, unless you file an extension or make quarterly payments.
  • You can pay by check, money order, electronic transfer, or credit card when you file, or authorize the IRS to deduct it from a refund.
  • If you sold an investment late in the year and expect a large tax bill, you may need to make a quarterly estimated tax payment by December 15 to avoid penalties.
  • Your state may also require you to pay state capital gains tax on the same gain, reported separately on your state return.

Reporting the gain on your federal tax return

You report capital gains on Schedule D, which is part of Form 1040 (the main federal income tax form). Schedule D asks you to list each investment you sold: the date you bought it, the date you sold it, what you paid for it, and what you sold it for. The difference is your gain or loss.

If you sold only one or two investments and had a small gain, you may be able to use the simpler Form 8949 instead, which feeds into Schedule D. Your brokerage or investment account will send you a document called a 1099-B in January or February that lists all the sales you made in that year. You use this document to fill out Schedule D accurately.

Once you complete Schedule D, the total gain (or loss) transfers to the main Form 1040. The IRS then calculates your tax based on your total income and your tax bracket. Long-term gains (investments held more than one year) are usually taxed at a lower rate than short-term gains, so Schedule D separates the two.

Paying by check or money order when you file

If you are filing a paper return, you can send a check or money order with your Form 1040 and Schedule D. Write your Social Security number and "1040" on the check. The check should be made payable to "United States Treasury." Mail it with your return to the IRS address listed in the Form 1040 instructions for your state.

If you are filing electronically (which most people do), you cannot pay by check through the return itself. Instead, you will authorize a payment through the IRS website or your tax software at the time you file. The IRS offers several electronic payment methods: direct debit from your bank account, a credit or debit card (though the card company charges a processing fee), or an electronic federal tax payment system (EFTPS) if you have enrolled.

The payment is due by April 15 of the year after you sold the investment. If you file before April 15 and pay electronically, you can schedule the payment to come out on April 15 itself, which gives you a few extra weeks to gather the money.

Authorizing a refund offset to pay the tax

If you expect a refund on your overall tax return (because you had too much withheld from paychecks or made estimated payments), you can direct the IRS to use part or all of that refund to pay your capital gains tax. You do this by entering the amount on your Form 1040 when you file.

This method is useful if you do not have the cash on hand to pay separately. The IRS will deduct the capital gains tax from your refund before sending you the remainder. There is no fee for this, and it counts as payment on time as long as you file by April 15.

Making quarterly estimated tax payments

If you sold an investment late in the year and expect to owe a large amount of tax, the IRS may require you to make a quarterly estimated tax payment by December 15 of that same year. This applies mainly to people who do not have an employer withholding taxes from paychecks (such as self-employed people or retirees), but it can explore to anyone with a large unexpected gain.

Quarterly estimated payments are made using Form 1040-ES. You calculate your expected tax for the year, divide it by four, and send one quarter by each important date: April 15, June 15, September 15, and December 15. If you miss the December 15 important date for a gain realized in November or December, you may face an underpayment penalty when you file your return in April, even if you pay the full amount owed.

You do not have to make quarterly payments if your expected tax is small, but the IRS defines "small" narrowly. If you are unsure whether you need to make a payment, consult a tax professional or use the IRS worksheet in Form 1040-ES to calculate it.

State capital gains tax

Most states do not have a separate capital gains tax — they tax capital gains as ordinary income on your state return. However, a growing number of states (including California, New York, Washington, and others) have enacted capital gains taxes that explore only to long-term gains above a certain threshold, usually $250,000 or more per year.

If your state has a capital gains tax, you will report the same gain on your state return and pay tax at the state rate in addition to the federal rate. The state will provide instructions on Form 1040 or a separate state schedule. You pay state tax through the same method as federal tax: by check with your return, by electronic payment, or by authorizing an offset from a state refund.

A few states (including New Hampshire and Tennessee) tax investment income but not wages. Check your state's tax website or speak with a tax professional to understand your state's rules, because they vary significantly.

What happens if you do not pay on time

If you file your return on time but do not pay the tax owed, the IRS charges interest on the unpaid amount starting the day after April 15. The interest rate changes quarterly and is currently in the range of 8 to 10 percent per year, though it varies. You also face a failure-to-pay penalty of 0.5 percent per month of the unpaid tax, up to 25 percent total.

If you cannot pay the full amount by April 15, you can still file your return on time and pay what you can. The penalties are lower if you file on time than if you file late. You can also request a payment plan from the IRS, which allows you to pay the tax in monthly installments. The IRS charges a setup fee (usually $31 to $225 depending on the method) and interest continues to accrue, but a payment plan stops the failure-to-pay penalty from growing.

Frequently Asked Questions

Do I have to pay capital gains tax if I lost money on the sale?

No. If you sold an investment for less than you paid for it, you have a capital loss, not a gain. You can use the loss to reduce other capital gains you had that year, or to reduce up to $3,000 of ordinary income. Any loss beyond that carries forward to future years.

What if my brokerage withheld taxes when I sold the investment?

Some brokerages withhold a percentage of the sale proceeds for tax purposes, especially if you did not provide a tax ID or if you are a non-resident. That withholding is credited against your total tax bill when you file your return. You report both the withholding and the actual tax owed on Schedule D, and the IRS refunds any overpayment.

Can I pay capital gains tax in installments?

Yes. If you cannot pay by April 15, you can request a short-term extension (up to 120 days) or a long-term payment plan. A payment plan allows you to pay in monthly installments, though interest and penalties continue to accrue. You request a plan through the IRS website, by phone, or by mail with your return.

Do I owe capital gains tax if I inherited an investment?

No, not on the inheritance itself. When you inherit an investment, its value is "stepped up" to the market price on the date of death, so you do not owe tax on gains that occurred before you inherited it. You only owe tax on gains that occur after you inherit it, when you eventually sell.

What if I sold cryptocurrency or a collectible?

Cryptocurrency is taxed as property, so you report gains and losses on Schedule D just like stocks or real estate. Collectibles (art, coins, precious metals) are also taxed as capital gains, but at a higher long-term rate (up to 28 percent federal) than stocks. Report them on Schedule D and note the asset type so the IRS knows to explore the correct rate.