How old do you have to be to use Polymarket? For the US app, Polymarket US, the answer in its exchange rulebook is 18, and you must also have reached the age of majority where you live. The App Store listing is rated 18+. This guide explains the rule, why it can mean an older age in a few states, and how it compares with Kalshi and sportsbooks, checked October 2026.
The rule
Polymarket US’s rulebook, filed with the CFTC in November 2025, says a participant must be at least 18 years old and have reached the age of majority in their state or country of residence. In most US states the age of majority is 18. In a few it’s higher, such as 19 in Alabama and Nebraska and 21 in Mississippi, so the minimum age there is effectively higher too. Polymarket verifies your identity when you sign up.
What about polymarket.com?
Polymarket’s main international exchange isn’t open to US residents at all, whatever their age. Outside the US, check Polymarket’s terms for the minimum age and whether the exchange is allowed where you live; local law can require a higher age. See Is Polymarket legal?
Why 18, when sportsbooks are 21?
Polymarket US and Kalshi are federally regulated exchanges for event contracts, like other CFTC-regulated markets, rather than state-licensed sportsbooks, which usually set 21 as the minimum. That difference is part of the wider legal argument over prediction markets; some apps, such as Novig, choose 21 anyway. See Kalshi age requirement and Are prediction markets gambling?
FAQ
Can you use Polymarket at 18?
Can you use Polymarket under 18?
Does Polymarket check your age?
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