FHIR®-based prior authorization is becoming one of the most significant areas of regulatory focus for Medicare Advantage, Medicaid, and commercial payers. Requirements tied to the CMS Interoperability and Prior Authorization Final Rule (CMS-0057-F) are accelerating the shift toward digital, structured, and highly coordinated exchange of clinical information.1 For managed care organizations and health plans, this shift affects technical infrastructure, data governance, and daily operations across utilization management, member services, and provider experience teams.
Review the high-level playbook health plans should use to take a practical, readiness-oriented approach and move from awareness to execution.
FHIR Expectations
FHIR is not optional for organizations responsible for utilization management.2 The CMS final rule establishes clear expectations for how prior authorization decisions will move across payers and providers through standardized APIs and structured datasets. CMS intends for these efforts to reduce administrative burden, shorten decision timelines, and give members and providers a more predictable experience across coverage transitions.3
But for payers, the adoption of FHIR is a big shift in how systems talk to one another and how information is validated, retrieved, and shared. This makes coordination, governance, and planning essential.
What most plans need now is a way to translate regulatory text into operational decisions, system changes, and repeatable processes that work in the real world.
Determine Your Operating Model Before Building
A plan can assemble working APIs and still fall short in production if the operating model behind them is unclear. Before starting technical work, health plans should define:
1. How the organization will behave as both a requestor and responder
Many plans underestimate the complexity of supporting outbound and inbound workflows at the same time. The policies, escalation paths, and documentation expectations differ across the two roles. Teams need clarity on which functions own each pathway, which systems they rely on, and what exceptions require manual review.
2. Which internal teams will own approvals, content standards, and change decisions
FHIR implementation creates a new category of ongoing governance. Plans must decide who reviews resource definitions, approves updates to mapping logic, and interprets CMS clarifications. If this is undefined until testing, testing slows down.
3. How delegated vendors, clinical partners, and UM subcontractors will participate
If an organization outsources UM, PBM functions, or care management, its vendors may generate or hold the very data that will appear in FHIR bundles. Plans should determine early whether vendors will generate FHIR-ready content or return raw data for the payer to assemble. Both models work, but each triggers different technical and contractual needs.
Clear operating models reduce friction later, when timelines tighten and technical teams need unambiguous direction.
Treat Data as the Hardest Part of Readiness
Most payers focus first on API configuration. In practice, the area that creates the most delays is data conditioning. FHIR only works if the underlying data is complete, normalized, and consistently mapped.
Plans should expect to spend more time validating data than building APIs. Common issues include:
- Granular clinical documentation existing in free-text fields rather than structured formats
- Inconsistent coding across legacy and modern sources
- PBM and UM systems that use internal code sets instead of standard vocabularies
- Delegated entities using formats that predate USCDI
- Gaps in historical data for members who transitioned from predecessor systems
The most successful organizations begin with structured data profiling. This identifies where values are incomplete, duplicated, or inconsistent when mapped to FHIR. Once those issues are documented, plans can decide whether to remediate data at the source, transform it during bundle assembly, or exclude certain fields using minimum necessary rules.
This level of analysis allows technical teams to design FHIR bundles that behave predictably under real-world coverage transitions rather than relying on idealized datasets.
Build APIs with the Production Burden in Mind
FHIR APIs require more than correct resource assembly. Health plans must ensure the final approach is stable at scale, supports rapid response expectations, and can withstand unplanned variations in inbound requests. Key considerations include:
Payload assembly performance: Plans should test how quickly their systems can construct complete bundles for high-volume or clinically complex members. FHIR responses accumulate rapidly as members age or move across programs. Without early performance testing, response times suffer and create compliance risk.
Payer identifier resolution: Plans will need reliable lookup logic to determine whether to treat another payer as an active exchange partner. If lookup processes rely on outdated directories or manual updates, response accuracy drops. This becomes especially challenging for members with frequent eligibility changes.
Error-handling logic that avoids ambiguous responses: FHIR requires precision in status codes. Plans should define rules for partial matches, incomplete data, and scenarios where information exists across multiple internal systems. Without carefully structured exception logic, payers may return responses that cannot be interpreted easily by receiving systems.
Logging that supports future audits: CMS will expect evidence of request handling, response timing, member matching, and error decisions. API design should include audit logging from the start rather than adding it after testing.
Strengthen Identity Matching Beyond Minimal Requirements
Identity matching is a primary source of payer-to-payer exchange failures. Plans often underestimate how member identifiers differ across programs, delegated entities, and historical systems. Invest early in match logic to avoid unnecessary denials, reduce manual review volume, and improve the reliability of FHIR responses.
A strong matching framework should evaluate:
- Which identifiers create the highest-confidence match
- How to treat differences generated by name changes, address updates, or inconsistent demographic fields
- Which scenarios require manual resolution rather than an automated response
- How member-initiated requests interact with identity verification processes
FHIR-based authorization is not a one-time compliance project. Standards evolve, CMS refines expectations, and vendors update their systems. Plans should establish ongoing governance that maintains:
- Updated mapping logic
- Revised capability statements
- Version-controlled documentation
- Procedures for evaluating CMS clarifications
- A method for monitoring API uptime, data quality, and response completeness
Moving Forward with a More Mature Readiness Strategy
FHIR prior authorization is a technical requirement, but the work you put in to make it sustainably successful is operational. If your team treats this as a system replacement project, you’ll face rework. Payers that treat it as a cross-functional redesign effort will meet deadlines with fewer production issues and clearer workflows.
Clearlink complements your technical FHIR implementation by strengthening the clinical and operational structures that support electronic prior authorization. Begin this work now create space for rigorous testing, thoughtful design, and fewer surprises during implementation.
If your plan needs support translating regulatory text into an actionable internal program, Clearlink can guide each stage from assessment through go-live. Get in touch to discuss how we can help your team prepare for the new operational demands ahead.
Sources:
1. CMS Interoperability & Prior Authorization Final Rule (CMS-0057-F), Centers for Medicare & Medicaid Services
2. 2.1.15 FHIR Overview, HL7 International
3. CMS Interoperability & Prior Authorization Final Rule CMS-0057-F Fact Sheet, Centers for Medicare & Medicaid Services