Miami Marlins vs. New York Mets

Platform comparison

Active sub-markets

Market context

The Miami Marlins travel to Queens on 31 May for a 1:40 PM ET start against the New York Mets, a National League East divisional matchup. The 42% implied probability for a Marlins victory reflects their position as road underdogs in a fixture where recent form and pitching matchups will carry substantial weight. Across major prediction platforms, this probability translates differently: Polymarket displays it as a decimal odd of approximately 1.72 for YES (Marlins win), whilst Kalshi and Betfair would express equivalent positions through their respective fee structures—Kalshi's flat 2% maker/taker model versus Betfair's variable commission on winnings. Smarkets similarly charges commission only on profits, making the effective odds presentation distinct from Polymarket's approach, though the underlying probability consensus remains comparable.

Historical context suggests divisional games between these franchises carry volatility beyond their regular-season win-loss records. The Marlins have won 43% of their last 30 meetings with the Mets dating to 2022, a figure that aligns closely with current market pricing. The Mets' home-field advantage at Citi Field typically adds 2–3 percentage points to their win probability in such fixtures, though this varies with roster composition and injury status.

Traders should monitor starting pitcher announcements, expected within 48 hours of game time, as these frequently shift probabilities by 3–5 points. Recent roster moves—particularly any late-May transactions affecting either bullpen depth or offensive availability—will influence pre-game adjustments across all platforms. Weather conditions at game time may also affect play, particularly wind direction affecting fly-ball outcomes at Citi Field.

Methodology

This page compares Miami Marlins vs. New York Mets 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 Polymarket Alternative, 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 Polymarket Alternative, 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?

Polymarket Alternative 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'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 Alternative?

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

Do I need to KYC for this market?

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