Polymarket odds for US-Iran ceasefire by Aug 31 rise to 58.5%

Polymarket Ceasefire Ladder Reprices After Reports of Overnight U.S. Strikes in Iran

Polymarket traders pushed the implied odds of an “effective US x Iran ceasefire by August 31” up to 58.5% on $1,488,626 in volume, a 5.0-point move higher. The repricing follows headlines about overnight U.S. strikes in Iran, and this ladder market shows how timing expectations shift across multiple deadlines.

Key Takeaways

Market-implied favorite is “Effective ceasefire by August 31” at 58.5% (No 41.5%).
After reports of overnight U.S. strikes in Iran, the ladder repriced toward a later ceasefire window rather than near-term deadlines.
Contract resolves by 2026-08-31 23:59 UTC; the leading line is up 5.0 points over both 24h and 7d.

A report said overnight U.S. strikes hit two provinces in Iran, leaving one person dead and several others wounded. The headline framed the incident as a fresh escalation, which serves as the immediate catalyst traders are mapping into ceasefire timing odds.

Odds Snapshot: $1.49M Volume Puts “Ceasefire by Aug 31” at 58.5% vs Aug 14 at 43.0% and Jul 31 at 31.5%

This is a price-ladder (deadline ladder) market: each strike is a separate “ceasefire by X date?” contract, so the label is a cutoff, not a settlement price or a single yes/no event. The August 31 line leads at Yes 58.5% / No 41.5%, while nearer deadlines trade much lower—August 14 sits at Yes 43.0% / No 57.0% and July 31 at Yes 31.5% / No 68.5%, with the very near July 18 at Yes 0.3% / No 99.7%. The 24-hour and 7-day change are both +5.0 points with “strong” momentum and “strengthening” consensus, implying traders are converging on a ceasefire scenario but discounting a fast turnaround within days. At $1.49M in volume, the market is actively updating, and the step-down from 58.5% (Aug 31) to 43.0% (Aug 14) quantifies how much probability traders assign specifically to a two-week pause versus a later de-escalation window. The resolution timestamp (2026-08-31 23:59 UTC) makes the final strike the key settlement boundary, while earlier strikes function as tradable estimates of timing rather than a single binary outcome.

Watch whether odds lift on the earlier rungs (July 24, July 31, August 14) or stay concentrated on August 31; that split is the cleanest read on whether traders are shifting from “eventually” to “soon” ahead of the 2026-08-31 23:59 UTC resolution.

What Traders Watch Next on Polymarket: Earlier Deadline Rungs (Jul 24/Jul 31/Aug 14) vs the Aug 31 Anchor Contract

Zooming out from the ceasefire timing ladder, traders are also benchmarking the knock-on scenarios that can reprice the whole complex across Polymarket. Big attention is on 97.75% No in “Strait of Hormuz traffic returns to normal by July 31?” ($18,719,328 volume, +39.75pp), 78.5% No in “Will the U.S. invade Iran before 2027?” ($45,375,440, +10.0pp), and 42.0% leading “August 31” in “Iran full airspace closure by...?” ($4,803,643, +3.0pp). Taken together, these side contracts act as adjacent gauges for how traders are weighing shipping normalization, escalation risk, and operational constraints alongside the headline ceasefire timeline.

Odds Trend

Window	Change (pp)
24h	+5.0
7d	+5.0

By the Numbers

Platform: Polymarket
Market: US x Iran Effective Ceasefire by...? (2 week pause)
Contract type: Price strike ladder: each rung has separate Yes/No; Yes means the spot price is above that USD strike at settlement.
Resolution window: Aug 31, 2026 (UTC)
Status: Active (open for trading)
Volume: ~$1,488,626

Top strike rungs

Strike	Yes	No
August 31	58.5%	41.5%
August 14	43.0%	57.0%
July 31	31.5%	68.5%
July 24	21.0%	79.0%

+1 more strikes not shown