CMS-0057-F Payer-to-Payer API

The Payer-to-Payer API moves a patient's data between health plans: when a patient joins a new impacted payer (or holds concurrent coverage) and opts in, the new payer must request, and the previous payer must serve, up to five years of claims, encounter, clinical, and prior authorization data over a FHIR R4 Bulk Data exchange, by January 1, 2027.

Example

Readiness checklist
 1. Build both directions: the requesting flow for members joining you, and
    the serving flow for members leaving you.
 2. Implement the opt-in capture at enrollment and the identity-matching step
    between plans.
 3. Assemble the five-year lookback payload from the same USCDI classes the
    Patient Access API serves.
 4. Stand up the Bulk Data export ($export, async status polling, NDJSON
    output files).
 5. Gate the underlying FHIR resources in CI before exchange testing with a
    partner plan:

pidgeon data install fhir-us-core-6.0   # package id says 6.0; installs US Core STU 6.1
pidgeon conform \
  --endpoint https://fhir.example.com \
  --ig http://hl7.org/fhir/us/core/ \
  --walk --ci

pidgeon conform validates resource instances the endpoint serves; it does not exercise the Bulk Data $export flow itself. Use it to produce conformance evidence for the resources inside the export before partner testing.

Validation context

Strict and compatibility validation notes land here with the phase-1 data export.