Polymarket API Versions Explained

The venue's official API is moving from v1 to v2, with v1 documented as retired on a schedule (late 2026 in current docs); the recorded archive's API is versioned and stable with breaking changes released through proper version bumps.

The honest habit is treating versions as calendar objects: an integration pinned to a retiring endpoint is a migration ticket you already own.

Pin the client to the targeted version, keep a layer that maps endpoints, and test against the documented deprecation notice before the deadline. The official SDK and the client ranking both track v2 explicitly.

The non-negotiable is the breaking-change read: new params, renamed fields, and path changes surface in release notes, and a client that consumes release notes instead of liveness probes survives migrations quietly.

The recorded API keeps its versioning visible and its schema documented (schema), so a study pinned to the v1 schema remains reproducible even as new endpoints arrive — the same reproducibility standard as the dataset's DOI versioning.

Where the two versions collide, the guidance is simple: current state through the venue's API, recorded history through the archive's — and neither should be reached by the other's client assumptions.

"Which version am I calling?" is a production question, not a trivia one: the honest integration names its version in code and its deprecation date in its runbook — and this page exists so nobody finds out by 404.

• Client ranking
• API data
• Backtest API