Price gaps between Polymarket and Kalshi — October 2026
Across 120 markets listed on both Polymarket and Kalshi, the median gap between the two venues' prices was 0.5 cents on 19 October 2026. 10% of pairs differed by 2 cents or more, and two pairs differed by 10 cents or more. Kalshi was the higher of the two in 65 pairs, Polymarket in 36, and 19 were level.
By Alexander Korzh · Published · Updated
What we measured
DOXA matches the same market across venues. For this note we took every matched pair between Polymarket and Kalshi that DOXA trusts for its merged order book, and compared the two venues' Yes prices as they stood at about 22:00 UTC on 19 October 2026.
A pair was counted only when both sides:
- were open for trading;
- had a price updated within the previous 24 hours;
- had at least $1,000 of liquidity;
- were priced between 2 and 98 cents.
120 pairs passed. The gap is the absolute difference between the two Yes prices, in cents.
How large the gaps were
| Gap | Pairs | Share |
|---|---|---|
| 1 cent or more | 50 | 41.7% |
| 2 cents or more | 12 | 10.0% |
| 3 cents or more | 6 | 5.0% |
| 5 cents or more | 2 | 1.7% |
| 10 cents or more | 1 | 0.8% |
The mean gap was 1.05 cents and the median 0.5 cents. Nine pairs in ten were within 2 cents of each other.
By category
| Category | Pairs | Median gap | Mean gap |
|---|---|---|---|
| Sports | 106 | 0.5¢ | 1.01¢ |
| Elections | 6 | 1.0¢ | 0.89¢ |
| Politics | 4 | 1.1¢ | 1.84¢ |
| Entertainment | 2 | 2.3¢ | 2.32¢ |
| Science and Technology | 2 | 1.0¢ | 1.03¢ |
Sports dominates the sample, because most markets listed on both venues are game lines. The other categories have too few pairs to draw a conclusion from.
The widest gaps
| Market | Polymarket | Kalshi | Gap |
|---|---|---|---|
| Baylor vs. Kansas (a spread line) | 31.5¢ | 19.0¢ | 12.5¢ |
| Arkansas-Pine Bluff vs. Florida A&M | 38.0¢ | 48.0¢ | 10.0¢ |
| Blue wave in 2026? | 83.5¢ | 79.0¢ | 4.5¢ |
| Copa Libertadores winner | 48.0¢ | 44.0¢ | 4.0¢ |
| #3 Spotify artist 2026 | 17.5¢ | 14.0¢ | 3.5¢ |
| NFC South champion | 17.5¢ | 20.0¢ | 2.5¢ |
The two largest gaps are college football lines with between $1,100 and $1,600 of liquidity on the thinner side. Gaps were widest where books were thinnest.
What the numbers do not show
- Not an arbitrage count. The prices are each venue's latest Yes price as DOXA last recorded it. They do not include fees, the bid–ask spread, or how much size is available at that price, so a gap does not mean a trade would have made money.
- One moment. This is a snapshot, not an average over the month. Game lines move quickly before kick-off.
- Only pairs DOXA trusts. Pairs that are not yet matched, or that are quarantined, are left out.
To see the venues side by side for a single event, open its comparison page, for example Blue wave in 2026?.