Chicago Cubs vs. Pittsburgh Pirates

Platform comparison

Active sub-markets

Market context

The Cubs travel to Pittsburgh on 25 May for a 1:35 PM ET matchup against the Pirates. Polymarket currently prices Cubs victory at 53%, reflecting modest favouritism despite Chicago's stronger recent record. The settlement window extends to 1 June, allowing for weather postponements common in late May baseball, though the contract resolves 50-50 only if the game is cancelled outright with no rescheduled date or ends in a tie—an exceedingly rare outcome in MLB.

Historical matchups between these National League Central rivals show the Cubs have held the upper hand in recent seasons, winning roughly 55% of their contests since 2020. However, the Pirates have proven competitive at home, where they've won approximately 48% of games over the same period. The current 53% probability for Cubs victory aligns closely with their baseline performance advantage, suggesting the market has priced in neither team's recent form nor home-field dynamics as a significant edge.

Traders should monitor starting pitcher announcements, typically confirmed 48 hours before game time, as rotation strength materially shifts win probabilities in baseball markets. Injury reports for key position players—particularly any late-inning bullpen unavailability—can shift conditional token prices on Polygon in the hours preceding first pitch. Weather forecasts for Pittsburgh should be tracked, as rain could trigger postponement and extend the settlement window. Recent Cubs and Pirates records heading into late May will provide context for any shifts in the 53% baseline as game day approaches.

Methodology

We track Chicago Cubs vs. Pittsburgh Pirates on the five venues with material liquidity for prediction markets. Live odds come from the Polymarket Polygon order book — the only source that ships real-time data under an open licence. For Kalshi, Betfair and Manifold we list platform attributes (fee, KYC, settlement, payment) instead of fabricated odds, because their APIs use non-comparable contract definitions.

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

Is this market available outside the US?

PolyGram is available in most jurisdictions where Polymarket isn't directly accessible. Polymarket itself is geo-blocked in the US/UK/EU. Always check local regulations.

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.

Do I need to KYC for this market?

Not under $1,500 of lifetime trading volume. Above that threshold, PolyGram triggers a quick verification flow that finishes in minutes.

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.