Chicago Cubs vs. Pittsburgh Pirates

Platform comparison

Active sub-markets

Market context

The Chicago Cubs face the Pittsburgh Pirates on 25 May at 1:35 PM ET in a regular-season matchup. The 53% crowd-implied probability favouring the Cubs reflects moderate confidence in Chicago's chances, though the Pirates remain competitive at implied odds around 47%. Across major prediction platforms, this market reveals structural differences: Polymarket displays decimal odds (approximately 1.89 for Cubs, 2.13 for Pirates), whilst Kalshi presents American moneyline format; Betfair's exchange mechanism allows lay betting unavailable on fixed-odds Smarkets. Fee structures diverge notably—Kalshi charges flat 2% on winnings, Polymarket takes 2% on both sides, and Betfair's commission scales with liquidity. KYC requirements also vary: Kalshi demands full US verification, Polymarket operates with lighter international access, and Smarkets accepts UK residents without US-level documentation.

Historical context suggests Cubs-Pirates matchups carry volatility. Over the past three seasons, home-field advantage in this rivalry has proven marginal; neither team has demonstrated consistent dominance in May fixtures. The Cubs' recent performance against sub-.500 teams and the Pirates' unpredictability against stronger opponents inform the relatively tight probability spread.

Traders should monitor starting pitcher announcements, which typically arrive 24–48 hours before game time. Injury reports for key position players—particularly any late-inning bullpen changes—can shift implied probabilities sharply. Weather conditions at PNC Park may favour certain playing styles. Settlement occurs 2026-06-01 at 17:35 UTC, allowing ample time for postponement resolution under the stated rules.

Methodology

This page compares Chicago Cubs vs. Pittsburgh Pirates specifically across Polymarket, Kalshi, Betfair Exchange and Smarkets. Live odds come from the Polymarket order book; the other venues' contract details are maintained manually because their APIs aren't directly comparable. Every CTA routes to PolyGram, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Polymarket settles via UMA Optimistic Oracle on Polygon. A proposer posts the outcome with a bond, the two-hour window runs, then the smart contract pays USDC.

Kalshi settles USD through the CFTC-regulated clearinghouse — the cleanest variant, with heavier KYC. Betfair Exchange settles in account currency (GBP/EUR), net of 2-5% commission. Smarkets follows the same model as Betfair with a lower default 2% commission.

FAQ

Where can I trade this market with the lowest fees?

On PolyGram, 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.

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.

What does it cost to trade on PolyGram?

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

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within 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.