Will the US confirm that aliens exist? Market odds

The markets

Will the US confirm that aliens exist?

Kalshi · 34.6M contracts traded

Outcome	Kalshi	Probability
Before Jan 20, 2029	19%
Before 2028	12%
Before 2027	4.5%
Before December	2.5%
Before November	1.5%
Before October	1%

Will the US confirm that aliens exist by…?

Polymarket · $70.9M traded

Outcome	Polymarket	Probability
September 30	<1%
December 31	3.5%

What to know

• The rules decide: these markets resolve only on an official US government confirmation as defined in each market's rules, not on sightings or reports.
• Base rate: no government has ever officially confirmed extraterrestrial life. Markets on events that have never happened tend to be priced above their true odds (the favorite-longshot bias).

How these markets resolve

• Kalshi, “Will the U.S. confirm that aliens exist?”: If the President, any member of the Cabinet, any member of the Joint Chiefs of Staff, or any US federal agency definitively states that extraterrestrial life or technology exists before Aug 1, 2026, then the market resolves to Yes. Full rules
• Polymarket, “Will the US confirm that aliens exist by...?”: This market will resolve to "Yes" if the President of the United States, any member of the Cabinet of the United States, any member of the Joint Chiefs of Staff, or any US federal agency definitively states that extraterrestrial life or technology exists by December 31, 2026, 11:59 PM ET. Full rules

How to read these odds

A price of 30¢ on a contract that pays $1 means the market puts the event at roughly 30%. Prices move with supply and demand, include fees and spreads, and can lean on long shots. When the two markets disagree by more than a few points, check whether their rules or deadlines differ. More in how prediction markets work and the favorite-longshot bias.

FAQ

What are the odds the US confirms aliens exist?

As of Sep 29, 2026, Kalshi prices it at 4.5% and Polymarket prices it at 3.5%. These are market prices, roughly the probability traders are willing to bet on, not a guarantee.

Why do Kalshi and Polymarket show different odds?

They are separate markets with different traders, fees and sometimes different rules or deadlines. A gap of a few points is normal; a large gap is worth checking against each market's rules.

How often are these odds updated?

Sikt refreshes this page from Kalshi's and Polymarket's public data several times a day. The time of the last update is shown at the top.

Are prediction market odds accurate?

Often, but not uniformly. Research on Kalshi finds prices are informative and improve as a market nears its close, but long shots tend to be overpriced (the favorite-longshot bias).