Houston Astros vs. Kansas City Royals

Platform comparison

Active sub-markets

Market context

The Houston Astros face the Kansas City Royals on 12 June at 8:10 PM ET in a regular-season Major League Baseball fixture. Resolution hinges on the official final score as recorded by MLB; postponement extends the settlement window until completion, whilst cancellation or a tied result (extremely rare in nine-inning play) triggers a 50-50 split. The settlement deadline of 20 June at 00:10 UTC provides a ten-day window for game completion and official confirmation.

The 88% crowd-implied probability reflects the Astros' stronger roster composition and recent divisional standing within the AL West. Historical matchups between these franchises show the Astros have maintained a winning record over the past three seasons, though the Royals' performance has improved incrementally. Comparable markets on similar regular-season fixtures between teams of disparate strength typically settle within a 10–15 percentage-point range of opening odds, suggesting the current probability sits within expected bounds for a matchup between a contending side and a rebuilding one.

From a regulatory standpoint, this market's accessibility depends on jurisdiction. Under German GlüStV provisions, prediction markets on sports outcomes remain restricted unless operating under specific licensing. In the US, CFTC oversight applies to certain event derivatives, though binary sports markets occupy a grey area pending further guidance. For UK traders, markets settling under £1,500 notional value typically fall outside KYC requirements on some platforms, though individual operators' terms vary. Traders should verify their platform's compliance posture before participation, as regulatory treatment of sports prediction markets continues evolving across major jurisdictions.

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). The odds column is filled only where we have clean data — that avoids the made-up numbers that get a network demoted when search engines cross-check against the source venue.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

FAQ

Where can I trade this market with the lowest fees?

On Polymarket Tax UK, which mirrors the Polymarket order book at 0% fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

What does it cost to trade on Polymarket Tax UK?

Zero. Polymarket Tax UK routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.