Platform comparison
| Platform | YES odds | NO odds | Fee | KYC | Settlement | |
|---|---|---|---|---|---|---|
PolyGram Pick polygram.ink |
100% | 0% | 0% (USDC on-chain) | No-KYC up to $1,500 | USDC, auto via UMA oracle | Open on PolyGram → |
Polymarket polymarket.com |
100% | 0% | 0% | Geo-blocked in US/UK/EU | USDC, on-chain | Open on PolyGram → |
Kalshi kalshi.com |
— | — | Up to 7% per trade | US-only, KYC required | USD | Open on PolyGram → |
Betfair Exchange betfair.com |
— | — | 2-5% commission | Full KYC from first trade | GBP / EUR | Open on PolyGram → |
Manifold Markets manifold.markets |
— | — | Play-money (mana) | None — play-money | Mana (no cash-out) | Open on PolyGram → |
Live odds for Polymarket-based markets come from the Polygon order book. Non-Polymarket venues show attributes only; clicking any row opens the market on PolyGram.
Market context
This market will resolve to "Up" if the Close price for S&P 500 (SPY) on May 21, 2026 is higher than the Close price for S&P 500 (SPY) on the most recent prior trading day. This market will resolve to "Down" if the Close price for S&P 500 (SPY) on May 21, 2026 is lower than the Close price for S&P 500 (SPY) on the most recent prior trading day. E.g., ordinarily, a market on Monday would refer to the previous Friday for its most recent closing price, unless that Friday were a market holiday, in
Methodology
We track SPY (SPY) Up or Down on May 21? on the five venues with material liquidity for prediction markets. Live odds come from the Polymarket Polygon order book — the only source that ships real-time data under an open licence. For Kalshi, Betfair and Manifold we list platform attributes (fee, KYC, settlement, payment) instead of fabricated odds, because their APIs use non-comparable contract definitions.
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?
- On PolyGram, which mirrors the Polymarket order book at 0% fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.
- Is this market available outside the US?
- PolyGram is available in most jurisdictions where Polymarket isn't directly accessible. Polymarket itself is geo-blocked in the US/UK/EU. Always check local regulations.
- 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 it cost to trade on PolyGram?
- Zero. PolyGram routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.
- 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.
Trade SPY (SPY) Up or Down on May 21? on PolyGram
Live order book, 0% fees, USDC settlement in seconds.
Trade on PolyGram →