S&P 500 (SPY) closes above … on July 23?

Platform comparison

Market context

SPY is trading around the mid-$740s, so this contract is about where the ETF prints at the closing auction rather than the day’s intraday range. On Polymarket, the position settles in USDC on Polygon through conditional tokens, so the practical question is whether the official SPY close lands above the strike level by the market close cut-off.[3][4][2]

The current 0% YES price is easiest to read as a threshold market that has already pushed far beyond the listed line, with Polymarket’s own event page showing the lower strikes at 100% while SPY itself has been quoted in the mid-$740s today.[2][3][1] Comparable markets on index ETFs tend to move only when the underlying is near the relevant level late in the session; when the ETF is hundreds of points above the strike, the remaining uncertainty is usually not about direction but about settlement mechanics and the final official close used by the market.[2][1]

A trader should watch the closing auction, any late-session volatility in the S&P 500 futures complex, and scheduled macro releases that can still affect the last print if they land before the 20:00 UTC settlement window ends.[2][1] The key dependency is the official SPY closing price used for resolution, not an average quote, so any headline or rebalance flow that hits near the bell matters more than earlier price action.[2][3]

Sources: 1 · 2 · 3 · 4

Methodology

We track S&P 500 (SPY) closes above … on July 23? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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.

FAQ

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 PolyGram. 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.

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.