HL7 FHIR · CMS Interoperability

FHIR APIs for CMS Interoperability Compliance

We build and stabilize HL7 FHIR R4 APIs — Patient Access, Provider Access, Payer-to-Payer, and Prior Authorization — for payers and the system integrators who serve them.

The mandates are published. The deadlines are fixed. We help you ship compliant APIs.

Interoperability Is No Longer Optional

CMS requires impacted payers — Medicare Advantage organizations, Medicaid and CHIP programs, and Qualified Health Plan issuers — to expose standards-based HL7 FHIR APIs.

Two final rules define the obligation. The Interoperability and Patient Access rule (CMS-9115-F) established the Patient Access API requirement. The Interoperability and Prior Authorization rule (CMS-0057-F) extends it with Provider Access, Payer-to-Payer, and Prior Authorization APIs, with compliance dates beginning January 1, 2027.

Patient Access API

CMS-9115-F · CMS-0057-F

FHIR R4 API giving members access to claims, encounter data, and clinical data — extended under CMS-0057-F to include prior authorization decisions.

Provider Access API

CMS-0057-F

In-network providers retrieve member claims, clinical data, and prior authorization information through a FHIR API with attribution and opt-out handling.

Payer-to-Payer API

CMS-0057-F

When a member changes plans, their data follows them. Payers must exchange member data with other payers over FHIR, including bulk exchange at scale.

Provider Directory API

CMS-9115-F

A public-facing FHIR API exposing provider directory data — names, network status, addresses, specialties — typically built on the Da Vinci Plan-Net implementation guide.

Prior Authorization API

CMS-0057-F

Providers query coverage requirements, submit prior authorization requests, and receive decisions — with status and reasons — through FHIR APIs built on the Da Vinci CRD, DTR, and PAS implementation guides.

FHIR Implementation, End to End

A compliant FHIR API is mostly not FHIR. It is the pipeline behind it: mapping claims, eligibility, and clinical data out of core administration systems into conformant resources — correctly, repeatably, and at scale.

HAPI FHIR Server Implementation

  • HAPI FHIR (JPA server) deployment and configuration
  • FHIR R4 resource modeling and profiling
  • Custom operations, search parameters, and interceptors
  • Performance tuning for member-scale workloads

Data Mapping & Conversion Pipelines

  • Claims and eligibility extracts to FHIR resources
  • X12 (837, 834, 278) to FHIR transformation
  • Terminology and code system mapping
  • Airflow-orchestrated, replayable ETL into the FHIR store

Access, Consent & Security

  • SMART on FHIR authorization flows
  • OAuth 2.0 / OpenID Connect integration
  • Member attribution, consent, and opt-out logic
  • Audit logging and access defensibility

Bulk Data & Payer Exchange

  • Bulk FHIR ($export) implementation
  • Payer-to-payer data exchange workflows
  • Large-scale backfill and reprocessing runs
  • Conformance testing against Inferno and Touchstone

HL7 FHIR R4 and the Required Implementation Guides

Core Standards

  • HL7 FHIR R4 (4.0.1)
  • US Core Implementation Guide
  • SMART App Launch Framework
  • Bulk Data Access (Flat FHIR)

Payer Implementation Guides

  • CARIN Blue Button (C4BB) for claims
  • Da Vinci PDex — payer data exchange
  • Da Vinci Plan-Net — provider directory
  • Da Vinci US Drug Formulary

Prior Authorization Guides

  • Da Vinci CRD — coverage requirements discovery
  • Da Vinci DTR — documentation templates and rules
  • Da Vinci PAS — prior authorization support
  • X12 278 integration where required

This Is a Regulated Data Pipeline Problem

FHIR compliance projects fail in the data layer, not the API layer. Standing up a HAPI FHIR server is the easy part — populating it correctly from claims, enrollment, and prior authorization systems is where deadlines slip. That data engineering is exactly what we do.

  • Deep experience with enrollment, eligibility, and adjudication data
  • Deterministic, replayable pipelines — built for audit defensibility
  • Airflow orchestration hardened for regulated workloads
  • Comfortable operating inside layered vendor chains
  • Senior capability, without heavy onboarding

How We Engage

We support payers directly or subcontract under prime system integrators delivering compliance programs. Whether you need a full implementation, remediation of a struggling one, or senior capacity added to an existing team, we integrate quickly and focus on shipping conformant APIs before the deadline.

The compliance dates are set,
and the implementation guides are published.
Let's talk about your FHIR roadmap.

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