Polymarket Tax Guide for US Traders: How the IRS Treats Prediction Market Winnings
Polymarket does not issue 1099 forms, but all trading gains are fully taxable and the IRS expects you to report them. The complication is that no one — not the IRS, not the tax courts, and not Polymarket itself — has definitively settled which of four possible tax frameworks applies. This guide explains each framework, the new rules that took effect in 2026, and what you need to track.
Disclaimer: This article is for informational purposes only and does not constitute tax advice. Tax laws are complex and subject to change. Consult a qualified tax professional for guidance specific to your situation.
The Core Problem: Four Possible Frameworks, No IRS Guidance
The IRS has not issued specific guidance on how prediction market income should be classified. Legal scholars and tax professionals have identified four possible frameworks, each with very different tax outcomes:
Framework 1: Short-Term Capital Gains
Under this treatment, each trade on Polymarket is treated as the disposition of a capital asset. If you buy YES shares at $0.60 and sell at $0.85, the $0.25 per share profit is a short-term capital gain (or loss). Short-term gains are taxed at ordinary income rates — the same bracket as your salary or freelance income.
Advantage: Capital losses offset capital gains, and up to $3,000 of net capital losses can offset ordinary income each year. This is useful for traders with mixed results.
Disadvantage: There is no preferential tax rate. Short-term capital gains are taxed at your full marginal rate, which could be 37% for high earners.
Framework 2: Section 1256 Contract Treatment
Some commentators argue that Polymarket contracts could be classified as Section 1256 contracts (the same category as regulated futures contracts). This would grant the 60/40 split: 60% of gains taxed at the long-term capital gains rate (up to 20%) and 40% at the short-term rate, with mark-to-market treatment at year-end regardless of whether positions are still open.
Advantage: The 60/40 split is the most tax-efficient framework for profitable traders. The effective tax rate on Section 1256 gains is typically 10-15% lower than ordinary income rates for high earners.
Disadvantage: Polymarket is almost certainly not a "designated contract market" under the Commodity Exchange Act, which means Section 1256 treatment is likely unavailable. Most tax professionals consider this the least defensible framework.
Trade with tools that track your history
Polysharp maintains detailed trade logs that simplify tax record-keeping — entry prices, exit prices, position sizes, and timestamps for every strategy execution.
Framework 3: Gambling Income
This is the framework many individual filers use by default. Net gains from Polymarket are reported as "Other Income" on Schedule 1, Line 8 of Form 1040 with a descriptive label like "Prediction market winnings." Gambling losses are deductible up to the amount of gambling winnings, but only if you itemise deductions.
Disadvantage (major): The One Big Beautiful Bill Act, signed into law on July 4, 2025, capped gambling loss deductions at 90% of gambling winnings starting with the 2026 tax year. This creates a brutal scenario for high-volume traders.
Consider a trader who generates $500,000 in winnings and $500,000 in losses over the year — net zero economically. Under the old rules, gambling losses fully offset gambling winnings and no tax was owed. Under the 2026 rules, only 90% of winnings ($450,000) can be offset by losses. The remaining $50,000 of winnings are taxed at ordinary rates. At 37% marginal rate, that is approximately $18,500 in federal tax on a year that produced no economic profit. State taxes add to the total.
Framework 4: Other Income (Non-Gambling)
Some tax professionals recommend reporting Polymarket gains as "Other Income" on Schedule 1 without characterising them as gambling income. This avoids the 90% loss cap but also means losses cannot offset gains for tax purposes (since capital loss rules would not apply). This framework is a middle ground that avoids the worst OBBBA implications but offers no loss benefit.
The 2026 Landscape: What the OBBBA Actually Changes
The One Big Beautiful Bill Act is the most significant tax change affecting Polymarket traders in 2026. The key provision — the 90% cap on gambling loss deductions — only applies if the gambling income framework is used. If you report under capital gains treatment, the cap does not apply. However, the IRS has broad discretion to reclassify your reporting if they disagree with your chosen framework.
This creates a genuine dilemma for 2026 filing. The gambling framework is the simplest and most commonly used approach, but it carries the 90% loss cap penalty for high-volume traders. The capital gains framework avoids the cap but requires more detailed record-keeping and carries the risk of IRS reclassification. There is no clear right answer for most traders.
Record-Keeping: What You Need to Track
Regardless of which framework you choose, proper record-keeping is essential. The IRS does not require a specific format, but any reasonable reconstruction of your Polymarket activity should include:
- Trade date and time for every entry and exit
- Contract description (market question, resolution criteria, outcome)
- Number of shares purchased or sold
- Price per share at entry and exit
- Gross proceeds from sales
- Fee-adjusted profit or loss per trade
- Wallet transaction hashes for on-chain verification
Recommended Approach: Crypto Tax Software
Manually reconstructing Polymarket trade history for tax purposes is not practical for anyone trading more than a few positions per month. Specialised crypto tax software can import your wallet history and generate the reports you need:
- CoinLedger: Directly supports Polymarket data import. Generates Form 8949 for capital gains treatment.
- Koinly: Imports Polygon blockchain activity and categorises trades. Supports multiple cost-basis methods.
- CountDeFi: Purpose-built for DeFi and prediction market tax tracking. Has a specific Polymarket integration.
Frequently Asked Questions
Do I need to pay estimated quarterly taxes on Polymarket gains? If you have significant Polymarket profits and no tax withholding covering the liability, estimated tax payments may be required to avoid underpayment penalties. This applies most commonly to traders who have substantial income outside of W-2 employment.
What if I only deposited $100 and never withdrew? If you deposited $100, made trades, ended the year with $50 in your wallet, and did not withdraw — you still have realised gains and losses on the trades you completed. The balance in your wallet is not the taxable figure. The tax liability is calculated on each trade as it occurs, not on your net deposit/withdrawal for the year.
Can the IRS track my Polymarket activity? Polymarket activity occurs on the Polygon blockchain, which is public and permanent. The IRS has invested significantly in blockchain analytics capabilities. While there is no automatic reporting from Polymarket, your on-chain footprint exists and is traceable by anyone with the right tools.
Detailed trade logs for stress-free tax reporting
Every trade executed through Polysharp is logged with entry/exit prices, timestamps, and position sizes — making tax record-keeping straightforward when tax season arrives.