Form 1099-B is the annual statement your brokerage sends when you sell stocks, funds, or other securities. It shows how much you received and, for most modern purchases, what you paid — the two numbers you need to calculate capital gains or losses.

What’s on Form 1099-B

A 1099-B lists each securities sale during the year. Key boxes include:

Box What It Reports
1a Description of property sold
1b Date acquired
1c Date sold
1d Proceeds (gross sale amount)
1e Cost or other basis
1f/1g Wash sale loss disallowed and adjustments
2 Whether gain/loss is short-term or long-term
4 Federal income tax withheld (if backup withholding applied)
5 Whether security is covered or uncovered
7 Whether basis was reported to IRS

Your brokerage’s consolidated 1099 statement may organize this differently, but all the required data flows from these boxes.

Covered vs. Uncovered Securities

Covered securities: Broker tracks and reports cost basis to the IRS. Applies to:

  • Stocks purchased on or after January 1, 2011
  • Mutual fund and ETF shares purchased on or after January 1, 2012
  • Most other securities purchased on or after January 1, 2013

Uncovered securities: Broker reports proceeds only — cost basis is not reported to the IRS. You must calculate your own basis and keep records. Common uncovered situations:

  • Stocks purchased before 2011
  • Inherited shares (basis stepped up to date-of-death value)
  • Gifted shares (generally carryover basis from the giver)

Calculating Gain or Loss

$$\text{Capital Gain or Loss} = \text{Proceeds (Box 1d)} - \text{Cost Basis (Box 1e)} - \text{Adjustments}$$

Example: You sold 100 shares of XYZ for $5,200 (proceeds). You paid $3,800 (cost basis).

$$$5,200 - $3,800 = $1,400 \text{ capital gain}$$

If you held the shares more than one year: $1,400 long-term capital gain — taxed at 0%, 15%, or 20%.

If you held one year or less: $1,400 short-term capital gain — taxed at ordinary income rates.

2026 Long-Term Capital Gains Rates

Taxable Income (Single) Rate
$0 – $48,350 0%
$48,351 – $533,400 15%
Over $533,400 20%
Taxable Income (MFJ) Rate
$0 – $96,700 0%
$96,701 – $600,050 15%
Over $600,050 20%

Wash Sale Rule

If you sell a security at a loss and buy the same or substantially identical security within 30 days before or after the sale, the IRS disallows the loss under the wash sale rule. The disallowed loss is shown in Box 1g of your 1099-B, and it’s added to the basis of the replacement shares (so you get the tax benefit when you eventually sell for real).

Example: You sell 50 shares of ABC at a $600 loss on December 20. You rebuy ABC on January 10 of the next year. The $600 loss is disallowed; it becomes part of your basis in the new shares.

How to Report 1099-B on Your Tax Return

  1. Form 8949 — Report each transaction (or use your broker’s substitute 8949 statement)

    • Part I: Short-term transactions
    • Part II: Long-term transactions
    • Columns: Description, dates acquired/sold, proceeds, basis, adjustments, gain/loss
  2. Schedule D — Summarize Form 8949 totals

    • Short-term gains/losses go on Lines 1–7
    • Long-term gains/losses go on Lines 8–15
    • Net result flows to Form 1040
  3. Capital loss carryover — If your net loss exceeds $3,000, the excess carries forward indefinitely to future tax years.

Worked Example: Multi-Trade Scenario

Emma sold three positions in 2026:

Security Held Proceeds Basis Gain/Loss
200 sh AAPL 18 months $8,400 $6,200 +$2,200 LT
50 sh TSLA 6 months $4,100 $4,800 −$700 ST
Bond fund 3 years $3,500 $3,100 +$400 LT

Net long-term gain: $2,200 + $400 = $2,600 (taxed at preferential rates) Net short-term loss: −$700 (offsets other income; if no other gains, deductible against ordinary income)

Emma’s taxable income is $75,000. Her long-term gains of $2,600 are taxed at 15% ($390). The $700 short-term loss reduces her ordinary income.

Each 1099-B transaction is reported on Form 8949 and Schedule D — which summarizes your total gains and losses before flowing to Form 1040. The tax rate on those gains depends on your holding period and income level — see 2026 capital gains tax rates for the 0%, 15%, and 20% thresholds. If your losses exceed your gains, the surplus carries forward to future years — see capital loss carryover for the rules.

WealthVieu
Written by WealthVieu

WealthVieu researches and writes data-driven personal finance guides using primary sources including the IRS, Bureau of Labor Statistics, Federal Reserve, and Census Bureau.

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