Bitcoin Up or Down on May 31?

Platform comparison

Market context

The market tests whether Bitcoin's price at noon ET on 31 May 2026 will be higher or lower than its price at the same time on 30 May. Polymarket currently prices this contract at 0% YES, implying near-certainty that Bitcoin will move downward across that single calendar day. The settlement mechanism uses Binance's 1-minute candle closes, with conditional token payouts distributed via USDC on Polygon—meaning traders holding YES tokens receive full value only if the later candle closes above the earlier one.

A 0% probability on a 24-hour directional move is historically unusual for Bitcoin, which has exhibited intraday volatility averaging 1–3% even during periods of relative stability. Comparable single-day prediction markets on major assets rarely collapse to zero unless external factors—regulatory announcements, exchange outages, or force majeure events—create genuine settlement risk. The extreme pricing suggests either technical factors specific to this contract's liquidity pool or market participants assigning material probability to a price tie, which would resolve 50-50 and leave YES holders with partial recovery.

Traders monitoring this contract should watch for macroeconomic data releases scheduled near the settlement window, particularly US inflation figures or Federal Reserve communications that could trigger directional moves. Bitcoin's correlation with equity futures during North American trading hours remains a key dependency; any major stock market event on 31 May could override typical intraday range-bound behaviour. The Binance data feed itself carries operational risk—any exchange maintenance or API delays during the noon ET candle close would affect settlement precision, though Polymarket's historical track record with Binance feeds has been reliable.

Methodology

This page is a comparison snapshot: one live quote (Polymarket), four reference venues with their key attributes, and a single execution path — every trade button routes to Kalshi UK, 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?

On Kalshi UK, 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.

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.

What does it cost to trade on Kalshi UK?

Zero. Kalshi UK routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.

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.