Cross-venue spreads: the same event, two order books
Our matcher links Kalshi and Polymarket markets that settle on the same underlying rule (methods: exact title match, fuzzy title, rule text, and model-assisted matching with a confidence score). When both venues quote the same event, the gap between their mids is a cross-venue spread — before fees.
How we rank the pairs
Each row shows the latest archived mid (bid/ask midpoint, in cents per $1 contract) on both venues, the absolute spread between them, and the spread net of estimated round-trip taker fees. Pairs are ranked by that fee-adjusted figure — the higher it is, the more the two books disagree. The fee estimate is:
fee_adjusted_cents = |mid_k - mid_p| - 200 * (0.07 * Pk * (1 - Pk) + 0.06 * Pp * (1 - Pp)), where Pk and Pp are the Kalshi and Polymarket mids in dollars; Kalshi taker fee is 0.07*P*(1-P) per side and Polymarket taker fee is 0.06*P*(1-P) per side, doubled for a round trip (entry + exit).
Positive fee-adjusted spreads are not risk-free profit: venue rules, settlement sources, and timing can differ even for matched pairs. This table is a research view of disagreement between venues, not a trading signal.
Matched pairs right now
No matched pairs in the archive yet — the cross-venue matcher runs nightly and this table fills in as matches accumulate.