--- title: "Polymarket freezes trading as accounts are drained" description: "A major API outage pushed Polymarket into cancel-only mode, and one trader says $800,000 left his account." url: https://tech.skoop.news/polymarket-hack-users-report-drained-accounts-as-trading-hal-a8e4a3/ published: 2026-10-31T07:57:23.946547-04:00 modified: 2026-10-31T07:57:23.946575-04:00 section: "Tech & Apps" publisher: "skoop.news" language: en keywords: ["Polymarket", "Predictions Trading API", "Polymarket US", "Shayne Coplan", "United States", "William LeGate", "UTC", "Capital", "Car", "Predict.fun"] hashtags: ["#PredictionsTradingAPI", "#PolymarketUS", "#ShayneCoplan", "#tech", "#ai"] image: https://upload.wikimedia.org/wikipedia/commons/5/55/Smartphone_use_at_railway_station.jpg?utm_source=commons.wikimedia.org&utm_campaign=imageinfo&utm_content=thumbnail_unscaled --- # Polymarket freezes trading as accounts are drained > A major API outage pushed Polymarket into cancel-only mode, and one trader says $800,000 left his account. Published 2026-10-31 · Updated 2026-10-31 · Tech & Apps, [skoop.news](https://skoop.news/) ## In brief - A trader posting as Car said $800,000 was drained from his account, about 20 minutes before Polymarket halted all new trading. [[1]](https://beincrypto.com/polymarket-halts-trading-users-drained/) - Polymarket went into cancel-only mode after its Predictions Trading API had a major outage. [[2]](https://coincentral.com/polymarket-hack-users-report-drained-accounts-as-trading-halts/) - Polymarket said anyone impacted will be made whole. [[2]](https://coincentral.com/polymarket-hack-users-report-drained-accounts-as-trading-halts/) ## An $800,000 drain and a freeze A trader posting as Car said $800,000 was drained from his account, about 20 minutes before Polymarket halted all new trading. [[1]](https://beincrypto.com/polymarket-halts-trading-users-drained/) The breach affected users on Polymarket's international venue. [[2]](https://coincentral.com/polymarket-hack-users-report-drained-accounts-as-trading-halts/) Other users reported accounts drained of thousands of dollars after positions were sold without consent. [[2]](https://coincentral.com/polymarket-hack-users-report-drained-accounts-as-trading-halts/) CoinDesk confirmed that users with balances on the international platform saw their accounts drained. [[2]](https://coincentral.com/polymarket-hack-users-report-drained-accounts-as-trading-halts/) ## What happened on the platform Polymarket went into cancel-only mode after its Predictions Trading API had a major outage. [[2]](https://coincentral.com/polymarket-hack-users-report-drained-accounts-as-trading-halts/) Its status page flagged the outage at 18:05 UTC and said the exchange had moved to cancel-only mode while investigating an unnamed incident. [[1]](https://beincrypto.com/polymarket-halts-trading-users-drained/) During the freeze, users with open positions could cancel pending orders but could not buy or sell. [[1]](https://beincrypto.com/polymarket-halts-trading-users-drained/) Polymarket also paused its relayer, which sends token transfers and spending approvals on behalf of users' wallets. [[1]](https://beincrypto.com/polymarket-halts-trading-users-drained/) Trading on the international platform was initially paused for several hours while the company investigated, and has since resumed. [[3]](https://www.wired.com/story/polymarket-flagship-platform-hack-traders-lose-money/) Polymarket said all systems were operational as of 7:05 pm UTC. [[2]](https://coincentral.com/polymarket-hack-users-report-drained-accounts-as-trading-halts/) ## The company's response Polymarket said anyone impacted will be made whole. [[2]](https://coincentral.com/polymarket-hack-users-report-drained-accounts-as-trading-halts/) It declined to comment on how many traders were impacted and how much money was lost, but said it will refund impacted traders. [[3]](https://www.wired.com/story/polymarket-flagship-platform-hack-traders-lose-money/) Law enforcement in the UK was notified of the incident, according to the company. [[3]](https://www.wired.com/story/polymarket-flagship-platform-hack-traders-lose-money/) Polymarket has not named a cause, victim count, or loss total for the incident. [[1]](https://beincrypto.com/polymarket-halts-trading-users-drained/) ## The company and its rivals Polymarket is led by founder and CEO Shayne Coplan. [[2]](https://coincentral.com/polymarket-hack-users-report-drained-accounts-as-trading-halts/) It recently raised $1 billion in August 2026, led by 1789 Capital, and is now valued at $21 billion. [[3]](https://www.wired.com/story/polymarket-flagship-platform-hack-traders-lose-money/) The freeze came two days after rival prediction market Predict.fun lost $400,000 to attackers. [[1]](https://beincrypto.com/polymarket-halts-trading-users-drained/) Polymarket's head of experience, William LeGate, said affected users in June were being refunded in whole. [[1]](https://beincrypto.com/polymarket-halts-trading-users-drained/) The smart contracts holding user funds were not breached in June. [[1]](https://beincrypto.com/polymarket-halts-trading-users-drained/) ## What this means for you If you trade on Polymarket's international platform, you are in the group affected by the breach. [[2]](https://coincentral.com/polymarket-hack-users-report-drained-accounts-as-trading-halts/) Polymarket said anyone impacted will be made whole. [[2]](https://coincentral.com/polymarket-hack-users-report-drained-accounts-as-trading-halts/) If you use Polymarket US, the company's separate platform for people within the United States, the hack did not affect you. [[3]](https://www.wired.com/story/polymarket-flagship-platform-hack-traders-lose-money/) Trading on the international platform has resumed, and Polymarket said all systems were operational as of 7:05 pm UTC. [[3]](https://www.wired.com/story/polymarket-flagship-platform-hack-traders-lose-money/) [[2]](https://coincentral.com/polymarket-hack-users-report-drained-accounts-as-trading-halts/) ## Sources 1. [Polymarket Halts Trading as Users Report $1.4 Million Drained](https://beincrypto.com/polymarket-halts-trading-users-drained/) — Yahoo Finance 2. [Polymarket Hack: Users Report Drained Accounts as Trading Halts](https://coincentral.com/polymarket-hack-users-report-drained-accounts-as-trading-halts/) — CoinCentral 3. [Polymarket Halted International Trading After Hackers Drained Accounts](https://www.wired.com/story/polymarket-flagship-platform-hack-traders-lose-money/) — Wired Image: Photo (illustrative): Rawpixel.com / Wikimedia Commons, CC0 (https://commons.wikimedia.org/wiki/File:Smartphone_use_at_railway_station.jpg) --- Written from the sources above and checked twice (rules and an independent model) before publishing. How we work: https://skoop.news/how-we-work/ · Corrections: https://skoop.news/corrections/