Polymarket Taxes (2026): How to Report Crypto Prediction Market Gains

Polymarket doesn’t send you a 1099. It doesn’t report your trades to the IRS. And it doesn’t calculate your cost basis for you. But if you made money trading on Polymarket, you owe taxes on those gains — and the IRS is paying more attention to crypto income than ever.

Because Polymarket runs on the Polygon blockchain and settles in USDC, your tax situation is meaningfully different from trading on a regulated exchange like Kalshi. If you haven’t set up your account yet, our Polymarket deposit guide covers getting USDC onto the platform. The burden of tracking, calculating, and reporting falls entirely on you. This guide walks through exactly how to handle it.

Disclaimer: This is educational content, not tax advice. Tax law around crypto prediction markets is evolving. Talk to a CPA for advice specific to your situation.

The Big Difference: No 1099, No Safety Net

When you trade on Kalshi, you get a 1099-B at the end of the year showing every trade, your cost basis, and your gains. The IRS gets a copy too. It’s straightforward — the numbers match, you report them, done.

Polymarket gives you none of that. No 1099-B. No annual summary. No cost basis calculation. You’re responsible for tracking every transaction yourself.

That doesn’t mean your gains are invisible to the IRS. They’ve got blockchain analytics tools and they’ve been actively going after unreported crypto income. This is one of the key tradeoffs of trading on an unregulated platform versus a CFTC-registered exchange. The question isn’t whether they can find your Polymarket activity — it’s whether they choose to look. With billions flowing through the platform, the odds of increased scrutiny keep going up.

How Polymarket Gains Are Taxed

The IRS hasn’t issued specific guidance on crypto prediction markets, but the most widely accepted treatment is that Polymarket gains are taxed as capital gains on digital assets. Here’s how that works.

Short-Term vs. Long-Term

• Held less than one year: Short-term capital gain, taxed at your ordinary income rate (up to 37% federal)
• Held more than one year: Long-term capital gain, taxed at 0%, 15%, or 20% depending on income

Since most prediction market contracts settle within days or weeks, nearly all your Polymarket gains will be short-term. That means you’re paying your full income tax rate.

No Section 1256 Treatment

Unlike Kalshi, which is CFTC-regulated and may qualify for Section 1256’s favorable 60/40 tax split, Polymarket isn’t a regulated exchange. Your trades don’t qualify for Section 1256 treatment. Every gain gets classified by holding period, and since most contracts are short-term, you’re paying your full ordinary rate.

This is a real cost difference. A trader in the 32% bracket making $10,000 on Polymarket pays roughly $3,200 in federal taxes. The same gains on Kalshi under Section 1256 would be about $2,300. That’s a $900 difference on identical profit.

	Kalshi (Section 1256)	Polymarket
Tax treatment	60% long-term / 40% short-term	100% short-term
$10,000 gain at 32% bracket	~$2,300	~$3,200
1099 issued	Yes	No
Cost basis calculated	By exchange	By you

Could It Be Gambling Income?

Some tax professionals argue prediction market gains should be classified as gambling income rather than capital gains. Under gambling treatment, your wins get taxed as ordinary income and your losses are only deductible if you itemize — and only up to the amount of your winnings.

That’s a worse deal than capital gains treatment for most traders, because capital losses can be deducted more broadly. The IRS hasn’t definitively ruled on this for crypto prediction markets. Most traders and CPAs treat it as capital gains on digital assets, but this is where professional advice really matters.

Tracking Your Trades: What You Need

Since Polymarket doesn’t give you tax forms, you’ve got to build your own records. Here’s what to track for every trade.

For Each Position

Field	Example
Date acquired	2026-01-15
Market	”Will the Fed cut rates in March 2026?”
Side	YES
Shares purchased	200
Price per share	$0.42
Total cost (USDC)	$84.00
Gas fees	$0.15
Cost basis	$84.15
Date settled/sold	2026-03-19
Settlement/sale price	$1.00 (settled YES)
Proceeds	$200.00
Gain/Loss	+$115.85

Where to Get Your Data

1. Polymarket account: Your trade history shows buys, sells, and settlements with timestamps and amounts.
2. Polygonscan: Your wallet address on Polygon shows every on-chain transaction. Search your address to see all USDC movements.
3. Crypto tax software: Tools like Koinly, CoinTracker, or TokenTax can import wallet transactions and calculate cost basis. Some now support Polymarket specifically.

The USDC Complication

Trading on Polymarket requires USDC, which adds an extra layer of transactions to track:

1. Buy USDC on a centralized exchange (Coinbase, Kraken, etc.)
2. Transfer USDC to your Polygon wallet
3. Deposit USDC into Polymarket
4. Trade on Polymarket
5. Withdraw USDC from Polymarket
6. Transfer USDC back to an exchange
7. Sell USDC for USD

Technically, each step involving a crypto asset is a taxable event. But since USDC is pegged to $1.00, the gain on holding USDC itself is negligible. Most CPAs treat USDC transfers at par ($1.00 = $1.00) and focus on the prediction market trades themselves.

If USDC ever depegs significantly while you’re holding it, that gain or loss would need to be reported too. Unlikely, but worth knowing.

Reporting on Your Tax Return

Polymarket gains get reported using the same forms as other capital gains:

Form 8949

List each trade as a separate line item:

• (a) Description: e.g., “Polymarket - Fed Rate Cut March 2026 YES”
• (b) Date acquired
• (c) Date sold or settled
• (d) Proceeds (settlement payout or sale price)
• (e) Cost basis
• (h) Gain or loss

Since Polymarket doesn’t issue a 1099-B, check Box C (short-term, no 1099) or Box F (long-term, no 1099) for each trade.

Schedule D

Transfer your totals from Form 8949 to Schedule D, which summarizes your overall capital gains and losses for the year.

High Volume Traders

If you made hundreds of trades, listing each one on Form 8949 is impractical. You can attach a summary statement with trade-level detail and report just the totals. Crypto tax software generates these automatically.

Deducting Losses

Had a losing year on Polymarket? Those losses are worth real money at tax time:

• Offset capital gains: Polymarket losses offset gains from stocks, crypto, other prediction markets, or any capital asset
• Deduct against income: If net losses exceed gains, deduct up to $3,000 per year against ordinary income
• Carry forward: Unused losses carry forward indefinitely

This makes tracking losers just as important as tracking winners. Every losing trade reduces your tax bill.

One catch: if your gains get classified as gambling income, losses can only offset gambling winnings and only if you itemize. The line between prediction markets and gambling is blurry — for more on that distinction, see prediction markets vs sports betting. Another reason to talk to a tax professional about classification.

Gas Fees and Transaction Costs

Gas fees on Polygon for Polymarket transactions get added to your cost basis, reducing your taxable gain. They’re small — a few cents per transaction — but they add up over hundreds of trades.

Track gas fees for:

• Depositing USDC into Polymarket
• Each buy and sell
• Withdrawing USDC from Polymarket

If you bridge funds from Ethereum to Polygon, the Ethereum gas fee (which can be several bucks) is also part of your cost basis.

Common Mistakes

1. Thinking No 1099 Means No Taxes

Most common, most dangerous. The IRS doesn’t care whether Polymarket sends you a form. All income is reportable. With blockchain analytics getting better, the risk of getting caught is real and growing.

2. Only Tracking Winners

Your losses are worth money at tax time. Only track winners and you’ll overpay. Track every trade — win or lose.

3. Ignoring USDC On-Ramp and Off-Ramp

Buy USDC at $0.999, sell at $1.001 — that’s technically a taxable gain. In practice most CPAs treat it at par, but keep records of your exchange transactions just in case.

4. Mixing Personal and Trading Wallets

Use a dedicated wallet for Polymarket. Mixing personal crypto with prediction market trading makes record-keeping way harder and raises audit risk.

Crypto Tax Software That Supports Polymarket

Several platforms can import Polygon wallet transactions and generate the forms you need:

• Koinly: Imports wallet transactions, calculates cost basis, generates Form 8949 and Schedule D
• CoinTracker: Similar features with direct exchange integrations
• TokenTax: Handles DeFi and prediction market transactions

These run $50-$200/year depending on volume. If you’re actively trading on Polymarket, the time savings and accuracy are worth it.

Polymarket vs. Kalshi: Tax Comparison

If you trade on both, here’s how they stack up:

	Kalshi	Polymarket
1099 issued	Yes (1099-B)	No
Reports to IRS	Yes	No
Tax classification	Potentially Section 1256 (60/40)	Short-term capital gains
Cost basis tracking	Done by exchange	Done by you
Fee deduction	Automatic in 1099	Manual tracking required
Loss carryback	3 years (if Section 1256)	No carryback
Ease of filing	Straightforward	Requires crypto tax tools

For pure tax efficiency, Kalshi’s the better platform. But Polymarket offers different markets, higher liquidity on some events, and no trading fees, so plenty of traders use both. If you do, keep separate records for each and report everything together.

When to Get Professional Help

Talk to a CPA if any of these apply:

• Your Polymarket gains exceed $5,000 (see our guide on making money on prediction markets for context on realistic returns)
• You trade on multiple platforms or exchanges
• You’re not sure whether to classify gains as capital gains or gambling income
• You’ve got significant losses to deduct
• You’re a non-US resident trading on Polymarket
• You used leverage or complex trading strategies

A crypto-savvy CPA runs $200-$500 for a consultation. Given the lack of clear IRS guidance on crypto prediction markets, professional advice is especially valuable. And the cost’s deductible as a tax prep expense.

The Bottom Line

Polymarket doesn’t make your tax life easy. No 1099, no automatic cost basis, no clear IRS guidance on classification. But the obligation is real, and the IRS is getting better at tracking crypto income every year.

The smart play: use a dedicated wallet, track every trade, run your transactions through crypto tax software, and talk to a CPA if your activity is substantial. The traders who treat their prediction market activity as a legitimate financial endeavor — including the unglamorous tax part — are the ones who don’t get blindsided by the IRS.