Will the US confirm that aliens exist by 2027?

Platform comparison

Market context

A **Yes** share would pay out only if a US President, Cabinet member, Joint Chiefs member or federal agency definitively states that extraterrestrial life or technology exists before the end of 2026; a **No** share wins if that threshold is not met. The key point is that the market needs an *official, explicit confirmation*, not just discussion of UFOs, unidentified anomalous phenomena, or the release of documents about unresolved sightings.[1][4][6]

That is why the current 0% implied probability sits in line with the government’s long record of caution. The White House and Pentagon have repeatedly said there is no evidence that unexplained objects are extraterrestrial, and NASA’s 2023 review likewise found no evidence supporting alien origin.[1][11][13] Even the recent 2026 file releases have been framed as disclosure of records, not proof, with the Pentagon describing them as unresolved cases and not direct evidence of extraterrestrial life.[3][5][18]

For traders, the main catalysts are official statements and scheduled disclosures, not social media speculation or congressional testimony. Watch for any new White House, Pentagon, NASA or AARO releases on the war.gov/ufo disclosure process, plus hearings or briefings that might create headlines, but remember that this market resolves only if the wording crosses the line into a definitive government confirmation.[3][6][12] The recent reporting on the disclosure programme also shows the gap between public interest and evidential proof: documents can be declassified without changing the underlying official position.[5][9]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

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%.