Exchanges / Kalshi vs Polymarket
Head to head · data through Oct 6, 2026
Kalshi vs Polymarket: trading volume
Over the 30 days through Oct 6, 2026, Kalshi traded $66.89B and Polymarket $14.66B: $4.47B on its international exchange and $10.19B on Polymarket US. Kalshi is ahead: Kalshi had 82.0% of the two companies' combined volume, against 83.5% in the 30 days before.
Volume by window
Notional volume, contracts × $1. Kalshi share is of Kalshi plus both Polymarket exchanges.
| Window | Kalshi | Polymarket, total | International | Polymarket US | Kalshi share |
|---|---|---|---|---|---|
| Tue Oct 6, 2026 | $2.18B | $458M | $139M | $320M | 82.6% |
| Last 7 days | $18.50B | $3.72B | $1.07B | $2.65B | 83.3% |
| Last 30 days | $66.89B | $14.66B | $4.47B | $10.19B | 82.0% |
| 2026 to date | $257.14B | $99.11B | $70.91B | $28.19B | 72.2% |
| Since Jan 1, 2025 | $281.20B | $126.56B | $98.28B | $28.28B | 69.0% |
Weekly volume, last 52 weeks
Monday to Sunday. Polymarket includes both of its exchanges.
By month
| Month | Kalshi | Polymarket | Kalshi share |
|---|---|---|---|
| September 2026 | $60.85B | $13.07B | 82.3% |
| August 2026 | $40.03B | $8.48B | 82.5% |
| July 2026 | $41.05B | $12.99B | 76.0% |
| June 2026 | $33.00B | $14.86B | 69.0% |
| May 2026 | $17.91B | $8.83B | 67.0% |
| April 2026 | $14.81B | $10.16B | 59.3% |
| March 2026 | $13.07B | $11.22B | 53.8% |
| February 2026 | $10.44B | $8.22B | 56.0% |
| January 2026 | $9.55B | $7.97B | 54.5% |
| December 2025 | $6.58B | $5.40B | 55.0% |
| November 2025 | $5.81B | $4.34B | 57.2% |
| October 2025 | $4.40B | $4.12B | 51.6% |
| September 2025 | $2.86B | $1.65B | 63.5% |
| August 2025 | $874M | $1.10B | 44.2% |
| July 2025 | $740M | $1.27B | 36.8% |
| June 2025 | $782M | $1.33B | 37.0% |
| May 2025 | $664M | $1.34B | 33.2% |
| April 2025 | $460M | $1.31B | 26.0% |
| March 2025 | $521M | $1.41B | 27.0% |
| February 2025 | $187M | $1.53B | 10.9% |
| January 2025 | $175M | $2.65B | 6.2% |
Kalshi vs Polymarket: questions
Is Kalshi bigger than Polymarket?
Yes, by notional volume over the 30 days through Oct 6, 2026: Kalshi $66.89B, Polymarket $14.66B across both of its exchanges. On Tue Oct 6, 2026, Kalshi traded $2.18B and Polymarket $458M.
Why are there two Polymarket numbers?
Polymarket runs two exchanges: its original international exchange, which settles on-chain, and Polymarket US, a CFTC-registered exchange operated by QCX LLC. Each publishes its own volume, so Volume Race shows both and adds them together for this comparison.
How is volume measured for Kalshi and Polymarket?
As notional volume: contracts (Polymarket calls them shares) traded, times the $1 each pays out. Kalshi's figure comes from Kalshi's daily market data file, Polymarket's from its own volume API and Polymarket US's daily market report. Methodology.
Who has more sports volume, Kalshi or Polymarket?
Kalshi. Its sports volume alone, $55.93B over the last 30 days (84% of its total), was more than Polymarket's entire volume across both exchanges, $14.66B. Polymarket's international exchange publishes no sports split, so its exact sports share is not known.