What the 1099-B Form Reports About Your Investment Sales

The 1099-B reports the sale price and cost basis of stocks, bonds, mutual funds, and other securities you sold during the year

A Form 1099-B is a tax document your brokerage sends you when you sell an investment. It shows what you sold, how much you received, and what you originally paid for it. The IRS gets a copy too, so they can match it against the gains or losses you report on your tax return.

You receive a separate 1099-B for each brokerage account you hold. If you sold nothing that year, you won't get one. If you sold investments through multiple brokers, you'll get multiple forms — one from each.

The form arrives by January 31 each year and covers all sales from the previous calendar year. It does not include dividends, interest, or money you moved between accounts without selling.

Key Takeaways

• Form 1099-B lists each security you sold, the sale price, and your original cost basis so you can calculate your gain or loss.
• Your brokerage sends you one 1099-B per account, and the IRS receives an identical copy to verify your reported capital gains.
• The form arrives by January 31 and covers only sales completed in the previous calendar year, not holdings you still own.
• You need the 1099-B information to fill out Schedule D (capital gains and losses) on your tax return.

What information appears on the 1099-B

The form lists each sale in a separate row. For each transaction, you'll see the security description (the stock or fund name), the date you sold it, the number of shares or units, the sale price per share, and the total proceeds. It also shows your cost basis — what you paid for it originally — though this field is sometimes left blank if your brokerage didn't have that information on file.

Box 1a shows your total proceeds from all sales. Box 1b shows your total cost basis. The difference between these two numbers is your total gain or loss for the year, though this is a rough figure because it doesn't account for holding periods or wash sales.

The form also indicates whether each sale was a long-term or short-term holding. Long-term means you owned it for more than one year; short-term means one year or less. This matters because long-term capital gains are taxed at lower rates than short-term gains.

Why brokerages report this information

The IRS requires brokerages to report all securities sales so the agency can track whether taxpayers are reporting their gains and losses correctly. Without this reporting requirement, people could sell investments and straightforward not mention the transaction on their tax return.

When your brokerage sends you a 1099-B, they also send an identical copy to the IRS under your Social Security number. The IRS computer system matches the 1099-B data against your tax return. If you report a different gain or loss than what appears on the form, the IRS may flag your return for review.

When cost basis might be missing or incorrect

If you bought an investment before your brokerage started tracking it, or if you transferred shares from another brokerage, the cost basis field may be blank or marked as "not reported to IRS." This doesn't mean you don't owe tax on the gain — it means you'll need to find the original purchase records yourself.

Some brokerages also make mistakes. They may report the wrong purchase date, wrong number of shares, or wrong cost basis. If you spot an error, contact your brokerage and ask them to issue a corrected 1099-B. The IRS will receive the correction as well.

If you received shares as a gift or inheritance, the cost basis is usually the fair market value on the date you received them, not what the original owner paid. Your brokerage may not know this, so you may need to calculate it yourself and keep records separate from the 1099-B.

How to use the 1099-B on your tax return

You report the information from your 1099-B on Schedule D (Capital Gains and Losses), which is part of your federal tax return. You list each sale, the proceeds, the cost basis, and the gain or loss. Then you total your long-term gains and losses separately from your short-term gains and losses.

If your total is a gain, you owe tax on it at your ordinary income rate (for short-term) or at the long-term capital gains rate (for long-term). If your total is a loss, you can deduct up to $3,000 of it against your other income in that year. Any loss above $3,000 carries forward to future years.

You do not send the 1099-B itself to the IRS — you just use the numbers from it to fill out Schedule D. Keep your 1099-B with your tax records in case the IRS asks questions later.

Multiple 1099-Bs and how to organize them

If you hold accounts at more than one brokerage, you'll receive a separate 1099-B from each one. You'll need to combine the information from all of them when you fill out Schedule D. Some tax software can import 1099-B data directly from your brokerage, which reduces the chance of entry errors.

If you sold a large number of securities, your 1099-B may be several pages long. Some brokerages also provide a summary page at the beginning that totals all your sales for the year. Check whether your brokerage offers an online version you can read, since paper copies can be hard to read.

Frequently Asked Questions

Do I need to report a 1099-B if I had a loss?

Yes. You must report all sales on Schedule D, whether they resulted in gains or losses. Losses reduce your taxable income, so reporting them is to your benefit. The IRS receives a copy of your 1099-B regardless of whether it shows a gain or loss.

What if my brokerage didn't send me a 1099-B?

Contact your brokerage and ask for it. If you sold securities, they are required to send one by January 31. If they say you didn't sell anything, check your account history to confirm. If you did sell and they still won't send it, you can report the sale yourself using your own records.

Can I ignore the cost basis field if it's blank?

No. You still owe tax on the gain, which is the sale price minus what you actually paid. If the 1099-B doesn't show your cost basis, use your own records — brokerage statements, purchase confirmations, or account history. Keep those records with your tax return.

Does a 1099-B include dividends or interest I earned?

No. Dividends appear on a 1099-DIV, and interest appears on a 1099-INT. A 1099-B covers only the sale of the security itself. You'll receive separate forms for any dividends or interest paid during the year.

What if I sold the same stock multiple times in one year?

Your 1099-B will list each sale separately. You report each one on Schedule D. If you bought and sold the same stock at different prices on different dates, each transaction is its own line item with its own gain or loss.