Venue comparison
Polymarket vs Kalshi
Compare prediction-market platforms, probabilities, liquidity and real market questions — side by side.
Polymarket
Founded 2020. The largest crypto-native prediction market — settles in USDC on Polygon — plus a separate CFTC-licensed US exchange since December 2025.
Kalshi
Founded 2018. A CFTC-regulated designated contract market since 2020 — event contracts traded and settled in US dollars, international since late 2025.
The quick answer
Both venues run the same basic instrument: an order-book contract that pays $1 if an event happens, so its price reads as a probability. Kalshi is a US, CFTC-regulated exchange — dollars in, dollars out — strongest in economics, weather and sports, international since late 2025, and by mid-2026 reporting the larger venue by monthly volume. Polymarket is the biggest crypto-native prediction market — USDC on Polygon, global reach — strongest in politics, geopolitics and crypto, with a separate CFTC-licensed US exchange since December 2025. Prices for similar questions routinely differ between them, because wording, rules, fees and traders differ. That gap is not noise; it is information — and occasionally an opportunity.
Where Polymarket stands out
Breadth on world events
Politics, geopolitics and crypto are its home turf — the deepest books and the most granular questions, and its geopolitics markets are fee-free as of August 2026.
Global, crypto-native access
The main exchange settles in USDC on Polygon and serves traders in much of the world; no bank wire required where it operates. Since December 2025 a separate, CFTC-licensed exchange serves US users in regulated form.
Discovery
More listed questions per news event — when a story breaks it tends to have several angles tradable at once, which is exactly what a probability board thrives on.
Where Kalshi stands out
Regulated US structure
A CFTC-designated contract market since 2020 — the first built for event contracts. Trades and settles in US dollars with normal banking on and off ramps.
Economic data and sports
Inflation prints, Fed decisions, weather and a wide sports range are its signature markets — categories where it is often the deeper venue.
Scale in 2026
By mid-2026 reporting its monthly volume leads the industry, and it opened to most of the world in late 2025. Availability by state and country still varies — sports contracts are being contested in several US courts.
Related markets, priced live on both
Found by the 15-minute sweep: questions the two venues both carry right now. Related, not identical — wording, resolution sources and deadlines differ between venues, which is often exactly why the prices do. Each side links to its own market page.
Every current pair, with order-book verification, lives on the surebets scanner.
Why do they disagree?
Different traders
The two user bases barely overlap — many people cannot legally reach both venues — so the same news gets priced by different crowds at different speeds.
Different wording
“By December 31” against “before year end”, one resolution source against another: small drafting differences are real differences in what the contract pays on.
Different resolution rules
Each venue settles by its own rulebook. Two markets about the same event can genuinely deserve different prices when their rules diverge on edge cases.
Liquidity and depth
A thin order book moves further on the same trade. A gap between venues is often one thin book lagging, not new information.
Fees shape prices
Both venues now charge taker fees that peak near 50/50 markets, and the rates differ by venue and category — which nudges where resting orders sit.
Timing
Prices update trade by trade. Right after news, the venue with the faster crowd leads and the other catches up — the lag is visible on this board's 24-hour columns.
Fees
Polymarket
Makers pay nothing; takers pay a fee proportional to p × (1−p) — highest near 50/50 markets — at category rates from 0.04 to 0.07, with geopolitics at zero, as of August 2026. No Polymarket-side deposit or withdrawal charges. Current schedule: official fee docs.
Kalshi
Takers pay roughly 0.07 × price × (1−price) per contract — about 1.75¢ at even odds — with maker fees only on some markets. ACH transfers are free; card deposits cost up to 2%. Current schedule: kalshi.com/fee-schedule.
Both formulas make a 50/50 market the most expensive to take and a longshot nearly free — worth knowing before comparing thin edges across venues. Fees change; the official schedules above are the authority.
Availability
Moving target, so in outline only: Polymarket's global exchange is restricted in several countries (the UK and France among them) while its US exchange serves US users under CFTC licence; Kalshi is US- based, opened to most other countries in late 2025 with its own restricted list, and several US states are challenging sports event contracts in ongoing litigation. Check each venue's own pages for your jurisdiction — nothing here is legal advice.
See both venues as one landscape
PredictionBubbles is the layer above the venues: both exchanges' markets on one live board, sized by money traded and colored by probability, with 24-hour movement, related markets, and a scanner that flags linked markets whose prices disagree. The venue comparison above is not homework you have to do by hand — the board does it visually, every 15 minutes.
Questions
Is Polymarket better than Kalshi?
Neither is better outright. Polymarket has the deeper politics, geopolitics and crypto markets and the larger global crypto-native exchange; Kalshi is the CFTC-regulated, dollar-in dollar-out venue with the bigger economics, weather and sports range. Which is better depends on what you want to trade and where you live.
Is Kalshi better than Polymarket?
Same answer from the other side: Kalshi if you want a US-regulated exchange, USD banking and its economics and sports markets; Polymarket if you want its politics and world-events depth or trade in crypto. Many questions exist on both, priced slightly differently.
Why are their odds different?
Because the markets are similar, not identical: wording, resolution rules and deadlines differ, the traders are largely different people, fees differ, and thin order books lag fast ones. Small gaps are normal; the persistent ones are what the surebets scanner looks for.
Can I trade the same event on both?
Often a similar question is listed on both venues — this page's related-markets section shows live examples. Read both rule pages before treating them as the same bet: they resolve under different rules and can settle differently on edge cases.
Which has more markets?
On this board right now: 1558 Polymarket markets and 588 Kalshi markets meet the volume cut. Globally both list far more, and the mix shifts daily — Polymarket skews politics and world events, Kalshi skews economics and sports.
Which has more volume?
By mid-2026 industry reporting, Kalshi's monthly volume is the larger of the two, while Polymarket remains the biggest crypto-native prediction market. Both are in the billions of dollars per month, and the lead has changed hands before.
Are both available in my country?
It varies and it changes. Polymarket's global exchange is restricted in several countries and its US exchange serves US users under CFTC licence; Kalshi opened internationally in late 2025 with its own restricted list, and several US states are contesting sports contracts in court. Check each venue's own availability page for where you live.
Does PredictionBubbles let me trade?
PredictionBubbles is an information tool. We display prices published by Polymarket and Kalshi. We do not accept wagers, hold funds, or offer accounts.