Polymarket Order Cancellation: Handling Timeouts Without Duplicate Exposure

A cancel request can time out while the order is canceled, live, or partially filled.

Model the failure correctly

Keep order ID, intent, original size, cumulative fills, remaining size, cancel time, and observed status.

Collect evidence

Use cancel-pending and unknown states until an authoritative open-order or fill read resolves the outcome.

Build the control path

Never replace an uncertain order blindly because that can double market exposure.

Handle edge cases

For bulk cancellation, enumerate the target set and verify each terminal result individually.

Recovery procedure

On restart, load exchange state first, match known identities, and quarantine unknown live orders.

Production metrics

Alert on oldest pending cancel, unresolved exposure, rejection rate, and local/exchange count delta.

TierZero can help implement or review this architecture through our relevant engineering service.

Primary reference

See the official technical documentation and pin the exact API behavior used by your deployment.

Discuss your system with TierZero.