How Prediction Market Winnings Are Taxed

Understanding prediction market taxes starts with one fact: winnings are taxable income in the United States. You owe taxes whether or not you receive a 1099 form, and regardless of whether you withdrew the money to a bank account.

On March 15, 2026, a trader named Sarah checked her Kalshi account and saw $18,000 in profits. She'd started with $2,000 in January and ran a simple strategy: bet on chalk in March Madness. The favorites, the high seeds, the teams that were supposed to win. Most of the time, they did. By the Elite Eight, she'd turned two thousand into eighteen. Two days later, Kalshi sent her a 1099-MISC form. The number matched her account history to the penny. Sarah stared at the PDF and realized she had no idea what she actually owed, or what would happen if she just didn't deal with it.

Here's what Sarah needed to know, and what every prediction market trader needs to understand before April 15: the platform you use determines the prediction market taxes you owe. If Sarah had used Kalshi, she'd report gambling income on one line of her 1040. Simple, straightforward, done in ten minutes. If she'd used Polymarket instead, she'd be tracking blockchain transactions across multiple taxable events and filing capital gains forms for every trade. The two platforms look nearly identical when you're placing a bet. The tax obligations are completely different.

Traders get this wrong because prediction markets don't fit cleanly into existing IRS categories. The government treats contracts on regulated platforms like Kalshi as gambling, with the same rules as casino winnings or horse racing payouts. It treats crypto-based platforms like Polymarket as property transactions, with the same rules as selling Bitcoin or Ethereum. You need to know which bucket you're in before you can figure out what you owe. These classification differences are one of several critical concepts we cover across our how-to guides for navigating prediction market mechanics and compliance.

This guide walks through exactly what happens when you win, how to report it without triggering an audit, and what records you need to keep. Let's start with the baseline rule that applies everywhere.

The Short Answer: Yes, You Owe Taxes

You must report winnings even if the platform didn't send you a 1099, you didn't withdraw funds to your bank account, you reinvested everything into other trades, or your net profit for the year was negative after losses.

The $600 threshold you've heard about determines when platforms must send you a form, not when you must report income. Your obligation to report starts at $1 in profit. The IRS computers don't care whether you got paperwork. They care whether you made money.

When calculating prediction market taxes, you need to understand how losses work. Losses can offset gains, but only under specific conditions. On dollar-based platforms, losses are deductible only if you itemize deductions on your tax return, and only up to the amount of your gambling winnings. Let's say you won $5,000 but lost $3,000. You can deduct the $3,000, but only if itemizing saves you more than taking the standard deduction. For most people, it doesn't.

On crypto platforms, losses can offset capital gains from other investments like stocks or real estate. If your losses exceed your gains, you can deduct up to $3,000 against your regular income each year. Anything beyond that rolls forward to next year's taxes. This structural difference is one reason experienced traders prefer crypto platforms despite the added reporting complexity.

You need records for every trade: date, contract description, entry price, exit price, quantity, and net gain or loss. If the platform doesn't provide a year-end summary (Polymarket doesn't, as of April 2026), you're responsible for building your own. Here's how the IRS actually classifies what you're doing.

How Prediction Market Taxes Are Classified by the IRS

The IRS approach to prediction market taxes depends on whether you traded on a regulated U.S. platform using dollars or a decentralized platform using cryptocurrency. Understanding these distinctions is essential knowledge within our guide to prediction markets, where regulatory classifications shape both platform accessibility and trader obligations.

Kalshi Tax Reporting: Dollar Platforms Follow Gambling Rules

The IRS calls this: Gambling income

Why this matters: Kalshi operates as a CFTC-regulated exchange where U.S. users deposit dollars and receive dollar payouts. The IRS treats event contracts ("Will the Fed cut rates in March?" or "Will this team win the championship?") as bets on uncertain future outcomes, not investments in property or securities.

What you file: Report winnings on Form 1040, Line 8 under "Other Income," or on Schedule 1, Line 8b if filing electronically.

How you deduct losses: Schedule A (Itemized Deductions), Line 16. Losses are capped at your total gambling winnings for the year. You cannot reduce your adjusted gross income with gambling losses. That's the number the IRS uses to calculate your tax bracket. Losses only offset winnings if you itemize, and itemizing became rare after the 2018 tax law changes raised the standard deduction to $13,850 for single filers and $27,700 for married couples filing jointly (2023 figures).

When you get a 1099: For Kalshi tax reporting, platforms must issue a 1099-MISC if you won $600 or more during the calendar year. Kalshi began sending these forms in February 2026 following platform policy updates.

Polymarket Taxes: Crypto Platforms Follow Capital Gains Rules

The IRS calls this: Property transaction (capital gains and losses)

Why this matters: Polymarket operates on the Polygon blockchain using USDC, a stablecoin pegged to the U.S. dollar. The IRS treats cryptocurrency as property, not currency. Every trade involves multiple taxable events: converting dollars to USDC, using USDC to buy prediction market shares, settling those shares for USDC, and converting USDC back to dollars. Each step can generate a taxable gain or loss.

What you file: Form 8949 (Sales and Other Dispositions of Capital Assets) and Schedule D (Capital Gains and Losses). If you made 50 trades in a year, you'll have 50+ rows of data to report.

How you deduct losses: Capital losses can offset capital gains from other investments: stocks, crypto, real estate, anything. If your total losses exceed your gains, you can deduct up to $3,000 against ordinary income like your salary. Remaining losses carry forward to future years indefinitely. They don't expire. You can use them whenever you have future gains to offset.

When you get a 1099: Polymarket does not issue 1099 forms as of April 2026. U.S. users who accessed the platform before its January 2022 ban on American traders, or who used VPNs to bypass georestrictions, are responsible for calculating their own cost basis and reporting gains. Using a VPN to bypass restrictions doesn't exempt you from tax obligations. If the IRS discovers unreported income, the penalties apply regardless of whether your platform access was legal. (Our guide Can US users use Polymarket? covers the current access restrictions.)

Additional Polymarket tax consideration: If you held more than $10,000 in cryptocurrency across foreign exchanges at any point during the year, you may need to file FinCEN Form 114, the Report of Foreign Bank and Financial Accounts. Polymarket is registered in the British Virgin Islands and likely qualifies as a foreign financial account. The penalties for missing this filing are severe (thousands of dollars even for unintentional violations). If you traded six figures or more, hire a CPA who specializes in crypto. This is not a DIY situation.

How to Actually Report Prediction Market Taxes

Step 1: Know Which Rules Apply to You

Before you can file prediction market taxes, figure out which framework you're using.

Dollar platforms like Kalshi:

• You deposited U.S. dollars
• You received payouts in U.S. dollars
• The platform sent you a 1099-MISC if you won $600 or more
• The IRS treats this as gambling income

Crypto platforms like Polymarket:

• You deposited USDC or another stablecoin
• Trades happened on a blockchain
• No 1099 form was issued
• The IRS treats this as a property transaction subject to capital gains rules

Mixing them up on your tax return can trigger an IRS notice because each path requires different forms, different loss treatment, and different record-keeping.

Step 2: Gather Your Transaction Records

You need documentation for every trade: date, contract description, entry price, exit price, quantity, and net gain or loss. The IRS expects records created when you made the trade, not reconstructed from memory months later.

What you need for each trade:

1. Date the contract was entered
2. Contract description ("Fed rate decision March 2026" or "Chiefs Super Bowl 2026")
3. Entry price (what you paid per share or contract)
4. Exit price or settlement value (what you received when the contract resolved)
5. Quantity (number of shares or contracts)
6. Net gain or loss (exit value minus entry cost, minus fees)

Where to find it:

Kalshi: Log in → Account → Transaction History. Export as CSV. The Kalshi tax reporting process is simplified by year-end summaries starting in 2026. For 2025 and earlier, you'll need to manually compile trades from your account history.

Polymarket: No built-in export tool exists. Your options:

• Manual screenshots of each resolved market from your portfolio page
• Blockchain explorer like Polygonscan (search your wallet address to see every USDC transfer in and out)
• Third-party crypto tax software like CoinTracker, Koinly, TokenTax, or CoinLedger, which can import Polygon transactions by syncing your wallet

If the platform doesn't provide summaries, build your own. Open a spreadsheet. Create columns for each required field. The IRS doesn't care how pretty it looks. They care that you can substantiate every number you report.

Step 3: File the Right Forms

Kalshi Tax Reporting: Form 1040 Process

You won $4,200 on Kalshi in 2025. You received a 1099-MISC showing $4,200 in Box 3 (Other Income).

What you do:

• Enter $4,200 on Form 1040, Line 8
• Attach Schedule 1 if filing electronically (most tax software does this automatically)
• Label the income source: "Kalshi — Prediction Market Winnings"

If you also had losses:

Let's say you lost $1,800 on other trades. You can deduct them only if you itemize.

• Total winnings reported: $4,200 (Line 8)
• Itemized deduction: $1,800 (Schedule A, Line 16)
• Taxable gambling income: Still $4,200, because losses don't reduce your adjusted gross income. They only reduce taxable income if itemizing saves you more than the standard deduction.

Reality check: If your standard deduction is $13,850 (2023 single filer) and your only itemizable expense is $1,800 in gambling losses, you're better off taking the standard deduction. You'll pay tax on the full $4,200 in winnings. This is why most casual prediction market traders can't actually use their losses. They don't have enough other itemizable expenses to make itemizing worthwhile.

Polymarket Taxes: Form 8949 Requirements

When filing Polymarket taxes, each trade is a taxable event. Let's walk through a single contract from start to finish.

January 10, 2025: You buy $500 USDC on Coinbase. Cost basis: $500. This is a taxable event (USD converted to USDC), but if you convert immediately, there's usually no gain because USDC is designed to stay at $1.00.

January 11, 2025: You transfer $500 USDC to Polymarket and buy 500 shares of "Will the S&P 500 close above 6,000 on January 31?" at $1.00 per share. This is another taxable event: you're exchanging USDC (property) for prediction shares (different property). Your cost basis in those shares is $500.

January 31, 2025: The market resolves YES. Your 500 shares settle for $500 USDC. This is the main taxable event. You sold 500 shares. Proceeds: $500 USDC, which equals $500. Cost basis: $500. Gain or loss: $0.

February 1, 2025: You withdraw $500 USDC to Coinbase and sell it for $501 because USDC was trading slightly above $1.00 that day. This is a final taxable event: you sold USDC (property) for dollars. Proceeds: $501. Cost basis: $500. Gain: $1.

On Form 8949, you report two transactions:

Transaction 1:

• Description: "500 shares Polymarket S&P 500 contract"
• Date acquired: January 11, 2025
• Date sold: January 31, 2025
• Proceeds: $500
• Cost basis: $500
• Gain/loss: $0

Transaction 2:

• Description: "500 USDC"
• Date acquired: January 10, 2025
• Date sold: February 1, 2025
• Proceeds: $501
• Cost basis: $500
• Gain/loss: $1

If you made 50 trades in 2025, you'll have 50+ rows on Form 8949. Crypto tax software automates this. Manual entry is possible but tedious and error-prone.

Holding period matters:

• Short-term (held one year or less): Taxed as ordinary income at your regular tax bracket
• Long-term (held more than one year): Taxed at preferential capital gains rates (0%, 15%, or 20% depending on your total income)

Most prediction markets resolve within days or weeks, so nearly all gains are short-term. You pay your full ordinary income tax rate on the profit.

Step 4: Understand What Losses Actually Do for You

Gambling losses (dollar platforms):

• Deductible only on Schedule A (itemized deductions)
• Capped at total gambling winnings for the year (you can't deduct more losses than you have wins)
• Cannot create a net loss that reduces other income like your salary
• Requires documentation: betting slips, account statements, withdrawal records

Capital losses (crypto platforms):

• Offset capital gains from any source (stocks, crypto, real estate, anything)
• If losses exceed gains, deduct up to $3,000 against ordinary income like your salary
• Remaining losses carry forward to future years and never expire
• Form 8949 required for each transaction

Example: You made $10,000 on Polymarket prediction markets but lost $8,000 day-trading Ethereum.

• Net capital gain: $2,000
• Taxed at your short-term rate, which is the same as your ordinary income bracket

If you lost $12,000 on Ethereum instead:

• Net capital loss: $2,000
• You deduct the full $2,000 against ordinary income this year
• No carryforward because the loss was fully absorbed

You can't net trades without documenting every position. The IRS wants to see each transaction. Aggregating wins and losses into a single number ("I made $5,000 overall") is a common error that triggers audits because the IRS can't verify where the number came from.

Step 5: Set Aside Money for Estimated Tax Payments

If you made significant profits (say $10,000 or more in a quarter) and you're self-employed or don't have an employer withholding taxes from your paycheck, you may owe quarterly estimated payments to the IRS.

The safe harbor rule: You avoid underpayment penalties if you either owe less than $1,000 in total tax for the year, paid at least 90% of the current year's tax liability through withholding or estimated payments, or paid 100% of the prior year's total tax (110% if your adjusted gross income exceeded $150,000).

Example: You earned $40,000 at your W-2 job and $20,000 on Kalshi in 2025. Your employer withheld $6,000 in federal tax. Your total tax bill for the year on $60,000 income is roughly $9,000.

• You owe $3,000 more than what was withheld
• The IRS expects quarterly payments if you owe $1,000 or more
• If you didn't pay quarterly, you'll face an underpayment penalty

Quarterly due dates:

• Q1: April 15
• Q2: June 15
• Q3: September 15
• Q4: January 15 of the following year

Use Form 1040-ES to calculate and pay. Most tax software like TurboTax or H&R Block will estimate this for you based on your income.

Practical advice: If you win big early in the year, set aside money immediately. The standard recommendation is 25-30% of your winnings, but that's worst-case for high earners in states with income tax. Calculate your actual marginal tax rate to find your real number. Open a separate savings account labeled "taxes" and transfer the money the same day you withdraw from the platform. Spending it and scrambling in April is how traders end up on IRS payment plans.

The Mistakes That Trigger IRS Notices

"I didn't get a 1099, so I don't have to report"

Wrong. You owe taxes whether you received a 1099 or not. The $600 threshold determines when a platform must send you a form, not when you must report income. If you won $500, you still owe taxes. If you won $50, you still owe taxes. The obligation starts at $1 in net profit.

The IRS receives copies of every 1099 issued. Their computers match the forms to your tax return automatically. If you received a 1099 for $4,200 but didn't report it, you'll get an automated CP2000 notice. That's a letter proposing additional tax, plus interest and penalties. The IRS calls this a "math error" letter, but what really happened is their systems caught a mismatch between what was reported to them and what you filed.

If you didn't receive a 1099 but made $500, the IRS won't know unless they audit you for another reason and discover the unreported income during the review. At that point, you're facing back taxes plus penalties for late payment and interest. If the IRS believes you intentionally concealed income, you could face fraud charges and additional penalties.

Matthew Foreman, a tax attorney specializing in digital assets, explained to MarketWatch in March 2026: "The number one mistake I see with prediction market traders is assuming no 1099 means no reporting. The IRS doesn't need a form to assess tax. Your obligation exists whether the platform follows through on theirs."

"Can I write off losses even if I didn't win anywhere else?"

For gambling income on dollar platforms like Kalshi: No, not in any meaningful way.

Gambling losses are an itemized deduction. They only help if your total itemizable expenses (mortgage interest, state and local taxes, charitable donations, medical expenses, and gambling losses) exceed the standard deduction. For 2023, the standard deduction is $13,850 for single filers and $27,700 for married couples filing jointly.

Let's say you lost $5,000 on Kalshi and won $2,000. You can deduct up to $2,000 in losses, because deductions are capped at your winnings. But unless you have $11,850 or more in other itemizable expenses (mortgage interest, property taxes, large charitable donations), you're taking the standard deduction anyway. The gambling loss does nothing for you. You still pay tax on the $2,000 in winnings.

For capital losses on crypto platforms like Polymarket: Yes, with annual limits.

Capital losses can offset capital gains from any source: stocks, real estate, crypto, anything. If you lost $5,000 on Polymarket but made $8,000 selling Tesla stock, your net capital gain is $