# Optum Interoperability APIs (CMS Patient Access)

**Canonical:** https://apis.io/apis/optum/optum-interoperability-apis-cms-patient-access/  
**Provider:** Optum — https://apis.io/providers/optum/  
**Base URL:** https://apigw.optum.com/  
**Documentation:** https://www.optum.com/en/interoperability-apis.html

Optum Interoperability APIs (CMS Patient Access) is one of 166 APIs that [Optum](https://apis.io/providers/optum/) publishes on the [APIs.io](https://apis.io/) network. Tagged areas include FHIR, Patient Access, Interoperability, CMS, and Provider Directory. The published artifact set on APIs.io includes API documentation.

Optum's payer-side CMS Interoperability and Patient Access (CMS-9115-F) surface — Patient Access, Provider Directory and Payer-to-Payer exchange for the Optum behavioral and physical health plans. The former developer.optum.com/dataaccessandinteroperability ReadMe project no longer resolves (every path returned the portal shell when probed on 2026-08-14); the developer information is now published as per-plan PDF packets on optum.com, so there is no machine-readable contract for this surface.

## Machine-readable artifacts (1)

- **Documentation** — https://www.optum.com/en/interoperability-apis.html

## Other Optum APIs (12)

- [Optum Real (Medical) API](https://apis.io/apis/optum/optum-real-medical-api/)
- [Optum Ambulance Fee Schedule APIs API](https://apis.io/apis/optum/optum-ambulance-fee-schedule-apis-api/)
- [Optum Anesthesia Fee APIs API](https://apis.io/apis/optum/optum-anesthesia-fee-apis-api/)
- [Optum APC Calculator APIs API](https://apis.io/apis/optum/optum-apc-calculator-apis-api/)
- [Optum APC Cross Codes APIs API](https://apis.io/apis/optum/optum-apc-cross-codes-apis-api/)
- [Optum Apip API](https://apis.io/apis/optum/optum-apip-api/)
- [Optum Application.wadl API](https://apis.io/apis/optum/optum-application-wadl-api/)
- [Optum Attachment API](https://apis.io/apis/optum/optum-attachment-api/)
- [Optum Attachment Document API](https://apis.io/apis/optum/optum-attachment-document-api/)
- [Optum Attachment Status API](https://apis.io/apis/optum/optum-attachment-status-api/)
- [Optum Attachment Submission API](https://apis.io/apis/optum/optum-attachment-submission-api/)
- [Optum Authentication API](https://apis.io/apis/optum/optum-authentication-api/)

## Tags

FHIR, Patient Access, Interoperability, CMS, Provider Directory

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/apis/optum/optum-interoperability-apis-cms-patient-access/). The API's provider profile, Kin Score and agent-readiness rating are at https://apis.io/providers/optum/.