Market comparison
Nashville vs Boston
2 venues · 7 outcome rows · 1 comparable lines · event identity linked · 0 verified parity · active
Kalshi
Open venue ↗2 outcomes · $239K reported volume
Observed 34s ago
Recorded venue end date: Oct 24, 2026
Polymarket
Open venue ↗6 outcomes · $116K reported volume
Observed 34s ago
Recorded venue end date: Oct 22, 2026
Known rule differences between venues
- Postponement: Kalshi resolves to a fair price if the game does not start within 48 hours of the scheduled time (tennis: not finished within two weeks); Polymarket stays open until the game is played and resolves 50-50 only if it is cancelled with no make-up (UFC/tennis: ~14 days).
- Ties and draws in two-way sports (NFL, college football, UFC no-contest): both venues pay 50/50.
- Soccer: both settle on 90 minutes plus stoppage time; extra time and penalties excluded.
- Tennis: Kalshi requires a ball to be played and pays the winner; Polymarket pays the player who advances, including on retirement. A pre-match walkover is a fair price on Kalshi, 50-50 on Polymarket.
- UFC: Kalshi ignores result changes after expiry; Polymarket follows the official UFC result.
- Polymarket two-way moneylines are one contract priced on the first-named side; the other side is its complement (recorded as a derived relation, not a link).
A shared identity alone does not make a price difference executable.
| Outcome | Kalshi | Polymarket | Difference |
|---|---|---|---|
Nashville Partial parityPayoffs match in ordinary outcomes; see the rule differences above. | 0.5 pp | ||
Boston Not alignedNo persisted outcome identity connects these venue contracts. | — | — | |
Predators vs. Bruins: O/U 4.5 Not alignedNo persisted outcome identity connects these venue contracts. | — | — | |
Predators vs. Bruins: O/U 5.5 Not alignedNo persisted outcome identity connects these venue contracts. | — | — | |
Predators vs. Bruins: O/U 6.5 Not alignedNo persisted outcome identity connects these venue contracts. | — | — | |
Predators vs. Bruins: O/U 7.5 Not alignedNo persisted outcome identity connects these venue contracts. | — | — | |
Spread -1.5 Not alignedNo persisted outcome identity connects these venue contracts. | — | — |
Nashville
Partial parityPayoffs match in ordinary outcomes; see the rule differences above.
Kalshi
Polymarket
Price difference 0.5 pp
Boston
Not alignedNo persisted outcome identity connects these venue contracts.
Kalshi
Polymarket
—
Predators vs. Bruins: O/U 4.5
Not alignedNo persisted outcome identity connects these venue contracts.
Kalshi
—
Polymarket
Predators vs. Bruins: O/U 5.5
Not alignedNo persisted outcome identity connects these venue contracts.
Kalshi
—
Polymarket
Predators vs. Bruins: O/U 6.5
Not alignedNo persisted outcome identity connects these venue contracts.
Kalshi
—
Polymarket
Predators vs. Bruins: O/U 7.5
Not alignedNo persisted outcome identity connects these venue contracts.
Kalshi
—
Polymarket
Spread -1.5
Not alignedNo persisted outcome identity connects these venue contracts.
Kalshi
—
Polymarket
Prices are shown as percentages of a $1 payout. “pp” means percentage points. A dash means data is unavailable.