Large Regional Plan Among First to Go Live with CMS-0057 Foundations, Powered by Onyx 

By Naveen Chaudhary, Client Success Officer, Onyx  

We’re excited to share a meaningful milestone in the path toward CMS-0057 compliance: a large regional  health plan, in partnership with Onyx, is now live with key foundational elements of the Final Rule—well ahead of the deadlines for full compliance.  

This marks one of the first real-world implementations in the country and reflects not just a commitment to regulation, but a strategic investment in infrastructure that supports scalable, standards-based data exchange across both regulated and commercial lines of business—serving over 3.1 million lives.  

Building the Foundation Together 

This go-live is the result of strong collaboration between our team at Onyx and our health plan partner. From shared urgency to focused execution, we were aligned on a single goal: to make interoperability real, practical, and future-ready. 

Together, we deployed: 

• • Upgraded Patient Access APIs supporting claims and clinical data 

• • Refreshed Provider Directory endpoints aligned with CMS-0057 specs 

• • Historical and current data loads to enable continuity and transparency 

• • Seamless integrations with existing systems—delivered with minimal disruption 

• • Foundational FHIR Source Data for all Access APIs – Provider Access, Payer to Payer and the Roadmap for HEDIS 

• • PAA Metrics for the first CMS-0057 deadline for March 2026 

What We’re Learning: Keys to CMS-0057 Success 

Every implementation has its nuances, but a few consistent success factors have emerged: 

• • Partnership mindset – Regular working sessions, shared goals, and cross-functional alignment 

• • Defined ownership – Clear roles across compliance, IT, and business leadership 

• • Actionable tools – Beyond documentation, our playbooks clarify workflows and accelerate execution 

• • Phase-first delivery – Starting with Patient Access and Provider Directory builds momentum for what’s next 

“Your playbooks… it’s all spelled out. And man, they are clear as day. Just awesome.” 
— IT Program Manager, Large Regional Health Plan 

What’s Next: End-to-End CMS-0057 Readiness 

With the foundation in place, our teams are now focused on delivering the rest of the stack to meet the CMS Deadlines for Jan 1, 2027: 

• • Payer-to-Payer Exchange – Bulk FHIR APIs for seamless member data portability 

• • Provider Access APIs – Real-time access for point-of-care decision making 

• • Electronic Prior Authorization (ePA) – CRD, DTR, and PAS APIs for streamlined automation and UM Integration 

These next phases build on the groundwork we’ve already laid—accelerating time to value and setting our customers up for long-term success. 

Compliance is a journey. We help you navigate it with confidence 

This milestone shows what’s possible when the right teams come together with shared focus and practical tools. With CMS-0057 deadlines fast approaching—starting January 2026—there’s limited time to move from planning to implementation.

As more payers begin their compliance journeys, we’re continuing to learn, refine, and support every step forward.

Download our  CMS-0057 Guide to see how Onyx helps health plans go from mandates to measurable results.