Kalshi vs Polymarket: Will **real GDP** increase by more than 3.0% in Q3 2026

Last observed 2026-09-04 20:08 UTC. Prices and fees change constantly; the rules comparison is the durable part.

• SETTLEMENT_POLICY_MISMATCH — both venues publish settlement policy, but the published texts diverge
• REVISION_POLICY_MISMATCH — the venues publish different rules about data revisions
• SETTLEMENT_GUARANTEE_UNKNOWN — the venue does not publish enough settlement policy to prove what happens in every branch (missing data, cancellation, revision)

The Polymarket leg here is the global venue, which US accounts cannot trade; it is shown for the rules comparison only.

Capital lock-up: about 146.7 days until the later of the two contracts settles.

Kalshi fine-print grade: F (35/100)
−20 FAMILY_POLICY_INCOMPLETE: the rules omit terms this contract family requires — the measurement basis, the revision rule, or the missing-release branch its peers publish
−20 MISSING_CANCELLATION_POLICY: the rules never say what happens to open positions if the event is canceled, voided, or never takes place
−15 MISSING_REVISION_POLICY: the rules never say whether a later revision of the underlying number changes the outcome
−10 MISSING_NEGATIVE_BRANCH: the rules say what settles the contract Yes but never state what settles it No

What Kalshi publishes

If real GDP (as measured by the BEA’s seasonally adjusted and annualized Advance Estimate) increases by more than 3.0, then the market resolves to Yes. The market will close at 8:29 AM on the day of the expected release of the data. The market will expire at the first 10:00 AM following the release of the data for Q3 2026, or 3 months following that expected date of data release. Please note the Expiration Value is the one-decimal value published by the BEA.

Fees use each venue's published taker formula at the last observed price — see the fee calculator for any price.