Pronóstico: S&P 500 (SPX) Up or Down on July 22?

Platform comparison

Market context

Polymarket has this contract at 78% YES, so the market is leaning towards the S&P 500 finishing higher than the previous close by the 20:00 UTC settlement cut-off on 22 July. In practical terms, that means traders are pricing a continued upward drift rather than a sharp reversal, with the outcome decided by the official cash close rather than intraday highs and lows.

A 78% print is relatively strong for a same-day direction market, but it is not unusual when US equities are already trending and volatility is subdued. For a Polymarket user, the relevant comparison is not whether the index can move intraday, but whether it can finish above the prior session’s official close after US cash trading ends. On these contracts, the edge often comes down to whether the final hour of trading, or any late macro headline, changes the closing print by even a small amount.

The main things to watch are scheduled US data releases, any Federal Reserve commentary, and earnings headlines that can move the index in the afternoon session. The S&P 500 is also sensitive to Treasury yield swings and large-cap tech moves, so a modest risk-off shift late in the day can still flip an otherwise bullish tape. Because settlement is tied to the official close and paid in USDC via Polygon conditional tokens, the final minutes matter more than the broad intraday narrative.

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 Polymarket Qué Es, 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.

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 Polymarket Qué Es. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

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 does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

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.