Bitcoin Up or Down - August 17, 12:00AM-4:00AM ET

Platform comparison

Market context

This market tracks whether Bitcoin's price will move upward or remain flat during a four-hour window on 17 August between midnight and 4:00 AM Eastern Time. The resolution hinges on Chainlink's time-weighted average price (TWAP) feed for the BTC/USD pair—a methodology that smooths price data across the settlement period rather than relying on a single snapshot. A YES share pays out if the TWAP at the end of the window meets or exceeds the opening price; a NO share pays if it falls below. The current crowd probability of 100% YES suggests traders expect upward momentum or price stability during this specific four-hour slot.

Historical Bitcoin price movements during overnight US hours (midnight to 4:00 AM ET) show considerable volatility, partly because Asian markets are in full trading session whilst US equity markets remain closed. Between 2022 and 2024, Bitcoin's overnight TWAP shifts have ranged from modest gains of 0.5–1.5% to declines of similar magnitude, with no pronounced directional bias. The extreme confidence reflected in the current odds warrants scrutiny; such certainty in short-window price predictions is uncommon given Bitcoin's sensitivity to news flow and derivative liquidations, which can occur without warning during low-liquidity hours.

Traders should monitor announcements from major cryptocurrency exchanges regarding system maintenance or trading halts, which could artificially constrain price discovery during the settlement window. Broader macroeconomic releases—particularly any unscheduled Federal Reserve communications or geopolitical developments—can trigger sharp moves in the early morning hours. The Chainlink TWAP methodology itself is resistant to flash crashes, but sustained selling pressure from institutional liquidations or coordinated selling remains a material risk to the upside thesis.

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 Prediction Market UK, which mirrors the Polymarket order book directly.

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.

UK Frequently Asked Questions

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 Prediction Market UK. 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.

Is Polymarket legal in the UK?

Polymarket is accessible to UK traders but is not UKGC-licensed. It operates under US CFTC jurisdiction. UK residents face no domestic legal prohibition on using it, but UKGC consumer protections do not apply. For UKGC-regulated alternatives, Betfair Exchange and Smarkets offer similar prediction-style markets.

Do I pay tax on prediction market profits in the UK?

UKGC-licensed platform profits (Betfair, Smarkets) are typically tax-free gambling winnings for UK individuals. Polymarket profits involve USDC crypto transactions, which HMRC treats as Capital Gains Tax events. Keep full transaction records and report via Self Assessment if gains exceed £3,000 per tax year.

How do I deposit on Polymarket from the UK?

UK traders typically fund Polymarket via Coinbase UK, Kraken or Revolut — buying USDC with GBP and transferring to a Polygon-compatible wallet (MetaMask, Coinbase Wallet). Polymarket's onboarding walks you through the bridging process. Typical GBP-to-USDC conversion costs 0.5–1%.