You are trying to decide between Kalshi and Polymarket. Both let you trade on real-world events. Both are worth billions. Both promise to be more accurate than polls.
Here is the honest answer most guides won't give you: Kalshi is the better starting point for most people. Polymarket is the better tool for the 3% who trade professionally.
This guide breaks down exactly why — with the numbers, fees, market coverage, and the specific traders each platform is built for. Updated August 2026 with the latest fee schedules, valuations, and regulatory changes.
Table of Contents
- The TL;DR: Which Should You Use?
- What Kalshi and Polymarket Actually Are
- Regulation and Legal Status
- Market Coverage: What You Can Trade
- Fees Compared (2026 Schedules)
- Liquidity and Volume
- Accuracy: Which Platform Is Right More Often?
- Funding Methods: USD vs Crypto
- Taxes and 1099 Reporting
- Frequently Asked Questions
The TL;DR: Which Should You Use?
Use Kalshi if: You are in the US, you want to fund with a bank account, you care about tax paperwork, you mostly trade Fed decisions, US politics, and mainstream sports.
Use Polymarket if: You want deeper liquidity on niche or global markets, you are comfortable with crypto and USDC, you follow international politics or crypto-native events, or you want zero maker fees.
Use both if: You are an active trader. Kalshi and Polymarket often price the same event differently, and the arbitrage between them is where much of the professional edge sits.
What Kalshi and Polymarket Actually Are
Both platforms are exchanges. You buy and sell binary contracts that pay $1 if you are right and $0 if you are wrong. Prices between $0.01 and $0.99 reflect the market's collective probability estimate.
Kalshi was founded in 2018 by Tarek Mansour and Luana Lopes Lara, both former hedge fund traders. It became the first federally regulated prediction market in the US, securing CFTC approval as a Designated Contract Market (DCM) in 2020. It runs on traditional financial infrastructure — no blockchain, no crypto required.
Polymarket was founded in 2020 by Shayne Coplan. It runs on Polygon (an Ethereum layer-2 blockchain) with recent expansion to Solana. Until 2025, it operated only internationally. In May 2026, Polymarket US launched as a CFTC-regulated exchange after acquiring QCX and QC Clearing.
Both are now legal in the US. Both are event contract exchanges. Where they differ is everything downstream.
Regulation and Legal Status
Kalshi has been federally regulated by the CFTC since 2020. That means:
- Segregated custodial accounts at regulated banks
- Public trade reporting to CFTC daily
- Mandatory KYC/AML on every user
- 1099 tax forms issued automatically
- Available in 40+ US states
Polymarket US operates under the same CFTC framework but only launched in May 2026. The larger Polymarket global exchange still operates offshore and has faced enforcement action from the CFTC in the past for operating an unregistered facility.
Both platforms are facing state-level legal challenges. Kalshi has been sued by New York, Nevada, Arizona, California, Massachusetts, and others. Polymarket is under CFTC probe tied to social media promotional conduct. Minnesota tried to ban both in May 2026 but a federal judge blocked the law in July.
Bottom line: both are federally legal. State-level access varies. Check the current list before signing up. Read our full analysis of the prediction market legal war for the latest state-by-state map.
Market Coverage: What You Can Trade
Kalshi's strengths
Kalshi lists 4,000+ markets across categories:
- Sports (80% of volume post-World Cup) — NFL, NBA, MLB, soccer, tennis, golf. Structured sports futures and daily lines.
- Economics — Fed rate decisions, CPI, GDP, employment. The deepest liquidity on macro contracts.
- Politics — US elections, congressional votes, cabinet appointments.
- Climate and weather — Hurricane strength, daily temperatures, snowfall totals.
- Culture — Oscars, Grammys, Billboard chart positions.
Kalshi's macro contracts are cited by CNBC, Barron's, and Bloomberg as leading indicators. Their Fed decision markets often move minutes before Fed funds futures react.
Polymarket's strengths
Polymarket lists 7,000+ active markets across categories:
- Global politics and geopolitics — the strongest category. Contracts on Iran, Russia, Ukraine, and other regions where Kalshi doesn't operate.
- Crypto — Bitcoin price milestones, ETF approvals, protocol upgrades. Native audience.
- US politics — 39% of volume post-World Cup. Deep liquidity on 2026 midterms.
- Breaking news — markets spin up within hours of major events. Faster than Kalshi.
- Niche categories — awards shows, celebrity news, viral culture markets.
Where Polymarket dominates: anything involving foreign events, crypto-native questions, or "will X happen by Y date" for hard-to-verify outcomes.
Fees Compared (2026 Schedules)
Kalshi fees
Kalshi uses a per-contract taker fee formula:
- Taker fee: $0.07 to $1.75 per 100 contracts, depending on market and price
- Maker fee: $0.02 to $1.75 per 100 contracts on certain markets
- Peak fee: around 50-cent contracts
- Debit card deposit: 2% third-party processor fee
- ACH/wire deposit: free
Polymarket fees
Polymarket uses a symmetric taker-fee model:
- Taker fee: $0.03 to $1.75 per 100 contracts, based on price and category
- Maker fee: 0% — completely free for makers
- Peak fee: around 50-cent contracts
- Geopolitical markets: zero fees
- USDC deposit: free (Polygon gas fees apply, usually under $1)
Real cost example
Buying 100 contracts at $0.50 on the September Fed hike market:
- Kalshi: $50 stake + ~$1.75 taker fee = $51.75 (3.5% cost)
- Polymarket US: $50 stake + ~$1.75 taker fee = $51.75 (3.5% cost)
- Polymarket Global (via USDC): $50 stake + ~$0.50 combined = $50.50 (1% cost)
For most trades under $100, fees are roughly comparable. The advantage kicks in for makers (Polymarket wins) and for large trades where Polymarket's international liquidity absorbs size better.
Liquidity and Volume
June 2026 volume snapshot:
- Kalshi: $31.5 billion (record month, up from $17.9B in May)
- Polymarket: $10.8 billion combined US + global
- Combined industry: $44.8 billion (record)
Kalshi holds roughly 67% of combined weekly volume as of Q3 2026. But volume differs by category:
- Sports markets: Kalshi dominates 80/20
- US politics: Polymarket dominates 60/40
- Global geopolitics: Polymarket is essentially alone
- Fed and macro: Kalshi leads on volume, Polymarket often leads on price discovery
For any specific market, check the bid-ask spread and order book depth before you trade. A platform with strong overall volume can still have thin liquidity on a specific contract.
Accuracy: Which Platform Is Right More Often?
Brier.fyi, an independent research site, tracks calibration across platforms using historical resolutions.
The 2026 data:
- Polymarket: Brier score 0.14 in politics, 0.18 in crypto
- Kalshi: Brier score 0.12 in economics, 0.16 in sports
- Both outperformed 964 opinion polls tracked by RealClearPolitics
The London Business School / Yale paper from April 2026 (analyzing $13.76B of trades) concluded that both platforms' accuracy comes from the same source: roughly 3% of skilled traders drive price discovery. The 97% of retail traders funds their profits. The platform doesn't matter as much as who is trading in your market.
Read our deeper analysis: The 3% Rule: Why "Wisdom of Crowds" Was Always a Myth
Funding Methods: USD vs Crypto
Kalshi funding
- ACH bank transfer — free, 1-3 business days
- Debit card — instant, 2% third-party fee
- Wire transfer — free, same day
- Crypto (USDC) — supported since late 2025
Polymarket funding
- USDC on Polygon — free (except gas), instant
- USDC on Solana — free, instant
- Fiat on-ramp via Coinbase or MoonPay — variable fees
- Bank transfer via Polymarket US — supported since May 2026
For users new to crypto, Kalshi wins on onboarding simplicity. For users already holding USDC, Polymarket is faster and cheaper.
Taxes and 1099 Reporting
Kalshi issues 1099 forms automatically at year-end and provides downloadable trade history. This makes tax reporting simple.
Polymarket does not issue tax documentation. US users must manually reconstruct trading history from on-chain transactions. This is doable but time-consuming and error-prone. For active traders, this alone can push you toward Kalshi.
Frequently Asked Questions
Is Kalshi or Polymarket bigger?
Kalshi is larger by volume, closing May 2026 with $17.91 billion in notional volume for its ninth consecutive monthly record, then hitting $31.5B in June. Polymarket posted $10.8B in June across its US and global exchanges combined. Kalshi's May 2026 valuation was $22B; Polymarket is currently in talks at $20B (up from $15B in April).
Is Polymarket legal in the US?
Yes, since Polymarket US launched in May 2026 with CFTC regulatory approval. The global Polymarket exchange is not directly legal for US residents but the US version now serves the American market.
Which has more markets?
Polymarket lists roughly 7,000 active markets across all categories. Kalshi lists 4,000+ markets. But Kalshi covers most of the mainstream categories users care about; the difference is Polymarket's coverage of niche, international, and viral markets.
Are the odds the same on both platforms?
Usually similar but not identical. When they diverge on the same event, that gap is a common source of arbitrage for skilled traders. Watch for divergence on Fed decisions, election contracts, and major geopolitical events.
Which has lower fees?
For small trades, roughly equal. Polymarket's zero maker fee is meaningful for active traders who provide liquidity. Kalshi's fees are lower on economics markets specifically. Polymarket's fees are waived entirely on geopolitical contracts.
Do I have to use crypto for Polymarket?
Yes, if you use the global platform. No, if you use Polymarket US, which accepts bank transfers. Kalshi accepts USD from bank accounts without any crypto involvement.
Which is safer?
Both are CFTC-regulated. Kalshi holds user funds in segregated custodial accounts at regulated banks. Polymarket US operates the same way; Polymarket global holds USDC in smart contracts on Polygon. Both have never experienced a security breach affecting user funds.
Can I use both?
Yes. Most active traders keep accounts on both and route orders to whichever platform has the better price for a given market. This is the professional approach.
What Juno Lets You Do
Juno's design borrows from both. Regulated infrastructure like Kalshi. Broad market coverage like Polymarket. Built for a market Kalshi and Polymarket don't serve: Thai users who want licensed access to event contracts without arguing with regulators about crypto.
You get the same event contract mechanics, the same probability pricing, in a jurisdiction that recognizes what you are doing.
Final Verdict
Kalshi is the safer default. Polymarket is the sharper tool. If you are new to prediction markets, start with Kalshi to learn the mechanics. If you become an active trader, add Polymarket for the markets Kalshi doesn't touch and the maker economics you can't get anywhere else.
Both platforms are legitimate financial infrastructure now, not the sideshow they were in 2022. The next five years will look more like a regulated derivatives industry than the Wild West era that got them noticed.
Article updated: August 29, 2026. Fee schedules, valuations, and volume data current as of Q3 2026.