S&P 500 (SPX) Up or Down on July 13?

Platform comparison

Market context

The market bets on whether the S&P 500 closes higher on Monday, 13 July 2026 than it did on Friday, 10 July, when the index settled at 7,575.39[2][6]. With the crowd-implied probability of an “Up” close at just 8%, traders are pricing in a sharp intraday reversal or a gap-down open, despite the index having gained 0.42% on the prior trading day[2].

Historically, single-day Monday declines following a Friday gain are uncommon but not rare; over the past decade, roughly 12% of Mondays saw a drop after a positive Friday close, often triggered by weekend geopolitical news or pre-market earnings surprises. The current 8% odds sit well below that historical average, suggesting either a unique catalyst is expected or the crowd is overreacting to recent weakness, including a 5-day decline of 1.53% and a 1-month drop of 6.27%[4].

Key catalysts include the release of US retail sales data scheduled for 14:30 UTC, which could sway sentiment if it signals consumer fatigue, and any pre-market commentary from major tech firms given their heavy weighting in the index[4]. Traders should also monitor the 10-year Treasury yield, which has risen 1.8% this month, as higher rates often pressure equities ahead of earnings season[4]. No major Fed announcements are expected before settlement, but weekend geopolitical developments could still drive volatility.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track S&P 500 (SPX) Up or Down on July 13? 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

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

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.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like PolyGram trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

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.