Kalshi vs Polymarket
The two biggest prediction markets, compared with live data instead of opinions. Updated Nov 8, 5:30 AM EST.
| Kalshi | Polymarket | |
|---|---|---|
| Regulation | CFTC-regulated US exchange | International site (non-US); Polymarket US is a separate CFTC-regulated app |
| Open to US users | Yes (some states contest it) | International site: no. Polymarket US: yes |
| Active markets we track | 2,670 | 5,548 |
| 24h volume (tracked markets) | $14.7M* | $150.3M |
| Wallet-level trade data | No | Yes (on-chain) |
| Contract payout | $1 per contract | $1 per share |
* Kalshi reports volume in contracts; we estimate dollars as contracts × price.
Which is cheaper right now?
Across the 174 games and races listed on both Kalshi and Polymarket US, the price to buy differs by a median of 1 points after taker fees. Kalshi is cheaper on 45% of them, and 25 differ by more than 2 points. See every game on the odds board, updated every 10 minutes.
Fees
| Kalshi | Polymarket US | Polymarket (intl, sports) | |
|---|---|---|---|
| Taker fee | 0.07 × C × p × (1 − p) | 0.0695 × C × p × (1 − p) | 0.05 × C × p × (1 − p) |
| Fee on 100 contracts at 50¢ | $1.75 | $1.74 | $1.25 |
C is the number of contracts and p the price. Kalshi rounds its fee up to the cent per order; maker orders and volume tiers can cost less. Check each venue's fee page before trading.
Where each venue's volume is
| Category | Kalshi markets | Kalshi 24h | Polymarket markets | Polymarket 24h |
|---|---|---|---|---|
| Sports | 842 | $8.3M | 2612 | $131.3M |
| Elections | 665 | $3.1M | 997 | $7.2M |
| Politics | 202 | $1.3M | 649 | $4.7M |
| Crypto | 49 | $513K | 309 | $2.9M |
| Science | 79 | $128K | 263 | $2.0M |
| Economy | 448 | $639K | 343 | $1.1M |
| Culture | 281 | $539K | 197 | $870K |
| Tech | 87 | $92.0K | 175 | $308K |
| Other | 14 | $29.6K | 3 | $248 |
| World | 3 | $75 | 0 | $0 |
Same question, both venues
The leading outcome on each venue, right now. A gap isn't free money: fees, spreads and different resolution rules usually explain it.
FAQ
Is Kalshi or Polymarket legal in the US?
Kalshi is a CFTC-regulated exchange (a designated contract market) open to US users, though several states are challenging its sports and election contracts in court. Polymarket’s main international site blocks US users; Polymarket US is a separate CFTC-regulated app for US customers with its own, smaller set of markets.
Which has better prices, Kalshi or Polymarket?
It depends on the market. Across the 40 questions we can match on both venues right now, the leading outcome’s price differs by 1 percentage points on average. Always compare the specific market, and read both venues’ resolution rules: small wording differences change what pays out.
Which has more markets?
Right now we track 2,670 active Kalshi events and 5,548 active Polymarket events that meet our minimum trading volume. Kalshi lists many small contracts (individual games, player props, local races); Polymarket concentrates volume in fewer, larger markets.
Can I see whale trades on both?
Only on Polymarket. Its trades settle on a public blockchain, so every trade has a wallet address. Kalshi publishes trades without account identifiers.