Polymarket pauses its international exchange for about an hour, citing a compromised third-party provider

What happened

Polymarket’s public status page records the incident as a “Major outage” of the “Predictions Trading API (CLOB)” component, with four updates on 29 October 2026:

• 2:05pm ET (18:05 GMT), Investigating. “The exchange is currently in cancel-only mode and relayer actions paused while we investigate an incident.”
• 2:37pm ET (18:37 GMT), Identified. “We have identified and fixed the issue impacting our international platform, Polymarket.com. One of our third party providers was compromised, and we have referred this to relevant law enforcement. Anyone who has been impacted will be made whole. Out of an abundance of caution, we have temporarily halted trading and are working to bring the platform back online.”
• 2:55pm ET (18:55 GMT), Monitoring. “Trading will resume at approximately 3pm ET.”
• 3:05pm ET (19:05 GMT), Resolved. “This incident has been resolved.”

Polymarket’s trader account on X, @PolymarketTrade, posted a statement in substantively the same words at 2:33pm ET (18:33 GMT), shortly before the status-page update. At 2:54pm ET (18:54 GMT) it said: “We are coming back online. Trading will resume at approximately 3pm ET.” At 3:00pm ET (19:00 GMT) it posted: “Trading is now fully back online. We’ll make this right and are fully reimbursing all affected traders.” The main @Polymarket account reposted that message at 3:01pm ET (19:01 GMT).

The status page puts the outage at one hour, from 2:05pm ET (18:05 GMT) to 3:05pm ET (19:05 GMT). For the first half-hour or so the exchange was in cancel-only mode; Polymarket announced the halt in its 2:33pm ET (18:33 GMT) statement.

What Polymarket has not said

As of 5:20pm ET (21:20 GMT) on 29 October 2026, Polymarket had not published a post-mortem on its status page or its X accounts, and had not:

• named the compromised provider or said what service it supplies
• described what users lost or how
• given the number of affected accounts or the amount to be reimbursed
• set out a timetable or process for reimbursement

Its statements refer only to its international platform, Polymarket.com. They do not say whether any other Polymarket platform was affected.

The UK position

Polymarket’s developer documentation lists the United Kingdom among “Regulatory-Restricted Jurisdictions (Close-Only on Frontend and API)”. It says users in those jurisdictions “can close existing positions but cannot open new ones, on both the frontend and the API”.

Why it matters

Polymarket has attributed the incident to a compromised third-party provider and has committed to reimbursing affected traders. It has not yet given the detail needed to judge the scope of the incident: which service was involved, what was lost, how many users were affected and how repayment will be made. Its status page carried no post-mortem as of 5:20pm ET (21:20 GMT).

What we are watching

• A Polymarket post-mortem or further statement naming the cause and scope of the incident.
• Details of the reimbursement process and timetable.
• Any statement from law enforcement on the referral.