S&P 500 (SPY) closes above … on July 13?

Platform comparison

Market context

On 13 July 2026, traders will settle positions based on where the S&P 500 (tracked by SPY) closes in regular trading hours. The 0% crowd probability reflects either extreme confidence in a bearish outcome or sparse liquidity in this particular strike; comparing books across platforms reveals material differences in how this uncertainty is priced. Polymarket's decimal-odds format and Kalshi's binary structure handle tail-risk scenarios differently, whilst Betfair and Smarkets' commission-based models create distinct breakeven thresholds for arbitrageurs. KYC requirements vary sharply—Kalshi operates under CFTC oversight in the US, Polymarket serves international users with lighter verification, and Betfair's UK-regulated status attracts European participants—meaning order flow and implied probabilities can diverge by 2–5 percentage points across venues for the same expiry.

Historical context matters here: the S&P 500 has closed below its 200-day moving average fewer than 15% of trading days since 2010, and single-day moves exceeding 3% occur roughly once per quarter. A 0% reading typically signals either a strike so far out-of-the-money that no trader bothers to quote it, or a technical glitch in probability aggregation. Comparable markets on major indices show that tail-strike probabilities often cluster near 1–3% on regulated platforms, suggesting this market may be mispriced relative to historical volatility.

Catalysts through July 2026 include Federal Reserve communications, corporate earnings revisions, and geopolitical developments affecting risk appetite. The settlement window closes at 20:00 UTC on 13 July, giving traders a hard deadline; traders should verify each platform's exact closing time, as some exchanges settle at 16:00 ET whilst others extend to post-market data feeds.

Methodology

This page compares S&P 500 (SPY) closes above … on July 13? specifically across Polymarket, Kalshi, Betfair Exchange and Smarkets. The live probability is the Polymarket mid; the comparison columns summarise each venue's fee structure, KYC, settlement currency and payment rails. Every CTA routes to Kalshi 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

Polymarket vs Kalshi — which is better?

Depends on your location. Kalshi is CFTC-regulated, US-only with full KYC. Polymarket is global, on-chain, no KYC up to $1,500. Polymarket has ~10x higher liquidity but higher regulatory risk.

What does Polymarket cost vs Kalshi?

Polymarket: 0% fees, only Polygon network costs (~$0.01/trade). Kalshi: up to 7% per trade plus spread. For high-frequency traders, Polymarket is dramatically cheaper.

Is Betfair a Polymarket alternative?

Only partially. Betfair Exchange is UK-focused with a sports-betting emphasis; they have politics markets but with thinner liquidity than Polymarket. Settlement in GBP/EUR, 2-5% commission on winnings.

What about Smarkets as an alternative?

Smarkets is a UK betting exchange with a lower default commission (2%) than Betfair. Liquidity on political markets is below Polymarket, comparable to Kalshi. Geo-blocked in many jurisdictions.

Are all these platforms regulated?

No. Kalshi is CFTC-regulated (US). Betfair and Smarkets are UK Gambling Commission licensed. Polymarket operates without explicit regulation — a different risk profile than a regulated sportsbook.