US x Iran Effective Ceasefire by September 30?

"US x Iran Effective Ceasefire by September 30?" resolved Yes on Sep 15, 2026; the market last priced it above 99% on Sep 15, 2026, and at 80% seven days earlier.

As of settlement on Sep 15, 2026. Source: Polymarket gamma API, market 4095055. Method and limitations.

The outcome is the venue's recorded resolution. The settlement date is the venue's own close timestamp; the scheduled end is the date the market was listed to close, which can differ.

Probability path

Last recorded YES price of each day, Sep 4, 2026 to Sep 15, 2026. Gridlines at 25, 50 and 75 percent.

From Sep 4, 2026, recorded YES prices ranged from 68% (Sep 9, 2026) to above 99% (Sep 15, 2026), across 375 recorded prices.

Weekly closes

How this market resolved

This market will resolve to “Yes” if there is a continuous 14-day period during which the United States does not take a qualifying military action against Iran that begins at any time between market creation and the specified date, 11:59 PM ET. Otherwise this market will resolve to “No.” The first day of the 14-day period will be the calendar date (ET) after the most recent qualifying military action (or the date of market creation, if no qualifying action has occurred). The period runs through 12:00 PM ET on the 14th calendar day. This market resolves to “Yes” if any such period is completed where the most recent qualifying military action occurred on or before the specified end date (ET). A qualifying military action refers to an air strike or a surface-to-surface missile strike, initiated by the United States, that directly impacts Iran. An air strike includes bombs, air-to-surface missiles, and air-launched drones. A surface-to-surface missile strike includes one-way attack drones and surface-to-surface missiles such as cruise or ballistic missiles. The following actions do not constitute a qualifying military action: Munitions destroyed or intercepted before impact; Surface-to-air missile strikes; Small-arms fire; Ground incursions; Cyber operations; Naval gunfire and artillery fire; Howitzers, artillery pieces, mortars, and rocket artillery (e.g. MLRS systems); Minor surface-to-surface strikes, including short range loitering munitions, FPV drones, and ATGM strikes; ...

Other settled outcomes in this event

Settled markets from the same event, with the venue's recorded outcome and settlement date.

More geopolitics markets

Live markets priced by the same venue, with their latest YES price.

Recently settled geopolitics markets

Dated records of markets that have settled, newest first.

Background reading

Evergreen explainers from Kresmion Learn on how prediction-market prices work.

Cite this data

Kresmion stored this market's YES price from the venue on a fixed capture schedule until settlement. The outcome is the venue's recorded resolution; the percentages are those stored prices, not a Kresmion estimate.

Upstream: Polymarket gamma API, market 4095055

Kresmion, "US x Iran Effective Ceasefire by September 30? (settled prediction market record)", data as of 2026-09-15, https://kresmion.com/odds/us-x-iran-effective-ceasefire-by-september-30. Upstream data: Polymarket gamma API, market 4095055.