Seattle Mariners vs. New York Yankees

Platform comparison

Market context

The Mariners travel to face the Yankees on 13 August in an afternoon matchup at 1:35PM ET, with the market currently pricing Seattle's chances at 41%. This represents a modest underdog position despite the Mariners' recent form—they've won six of their last ten games heading into late August, whilst the Yankees have maintained a stronger win rate over the same stretch. The 41% probability reflects both teams' competitive positioning within the AL playoff picture, where every game carries significance as the season enters its final weeks.

Historical matchups between these franchises show the Yankees hold a slight edge in head-to-head records over recent seasons, though the Mariners have proven capable of taking series in New York. The current probability sits near the midpoint of typical home-field advantage adjustments in baseball markets, suggesting traders are factoring the Yankees' home status without overwhelming confidence in their victory. Comparable games involving playoff-contending teams at this stage of the season typically see probabilities shift 3–5 percentage points based on pitching matchups and injury updates.

Traders should monitor lineup announcements and bullpen availability in the 24 hours before first pitch. Recent reports on key player availability—particularly any late-inning relievers or designated hitters—often trigger repricing in afternoon games. Weather conditions at Yankee Stadium could also influence scoring expectations; August heat and humidity occasionally favour teams with deeper benches. The settlement window extends to 20 August, allowing for postponement adjustments should weather force a reschedule.

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Prediction Today, which mirrors the Polymarket order book directly.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

UK Frequently Asked Questions

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is Prediction Today. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

Is Polymarket legal in the UK?

Polymarket is accessible to UK traders but is not UKGC-licensed. It operates under US CFTC jurisdiction. UK residents face no domestic legal prohibition on using it, but UKGC consumer protections do not apply. For UKGC-regulated alternatives, Betfair Exchange and Smarkets offer similar prediction-style markets.

Do I pay tax on prediction market profits in the UK?

UKGC-licensed platform profits (Betfair, Smarkets) are typically tax-free gambling winnings for UK individuals. Polymarket profits involve USDC crypto transactions, which HMRC treats as Capital Gains Tax events. Keep full transaction records and report via Self Assessment if gains exceed £3,000 per tax year.

How do I deposit on Polymarket from the UK?

UK traders typically fund Polymarket via Coinbase UK, Kraken or Revolut — buying USDC with GBP and transferring to a Polygon-compatible wallet (MetaMask, Coinbase Wallet). Polymarket's onboarding walks you through the bridging process. Typical GBP-to-USDC conversion costs 0.5–1%.