The Payer-to-Payer Data Exchange API is the technically heaviest of the four CMS-0057-F endpoints. A receiving payer requests a five-year history (clinical data, claims, encounters) from a prior payer when a member opts in during enrollment. The prior payer has one week to respond after coverage start, with one business day to deliver after the formal request. The transfer uses FHIR Bulk Data and depends on FHIR Member Match to confirm the member identity across systems. Most vendors that handle Patient Access well do not yet handle Payer-to-Payer at production scale. Here are six that do or are credibly close in 2026. For broader context, more FHIR for health plans sets the larger frame.
What Payer-to-Payer Actually Requires
The Payer-to-Payer flow is asymmetric. The receiving payer initiates with a $bulk-member-match operation against the prior payer to confirm member identity. The prior payer authenticates the request, resolves the match, and runs a $davinci-data-export to package the five-year history as FHIR Bundles. The data set excludes denied PAs and cost-sharing detail. Concurrent coverage adds quarterly sharing rules. Educational materials and the opt-in flow live on the receiving payer's side, typically inside the member portal.
1. Smile Digital Health (Payer-to-Payer Module)
Smile CDR ships Payer-to-Payer support that handles Member Match, Bulk Data export with five-year history, and FHIR Consent resources with full audit trail. The implementation has been tested across multiple payer-to-payer transitions in pilot. The data layer underneath is the same FHIR store powering Patient Access and Provider Access, which keeps consent state coherent across APIs.
2. InterSystems IRIS for Health
InterSystems IRIS handles Payer-to-Payer through the broader interoperability platform. The Bulk Data engine is mature; the Member Match implementation integrates with whatever member identity layer the payer already runs (often via the IRIS data tier). The trade-off remains the enterprise commercial model and longer integration runway.
3. 1upHealth Payer-to-Payer
1upHealth implements Payer-to-Payer with first-class Member Match and Bulk Data Access. The consent flow leverages the platform's existing OAuth and consent infrastructure. The model fits cloud-native payers well. The five-year history depth depends on how much historical data the payer has migrated into 1upHealth's FHIR store; recently migrated plans may not have the full window initially.
4. Edifecs Payer-to-Payer
Edifecs offers Payer-to-Payer Data Exchange as part of the broader CMS interoperability suite. The X12-to-FHIR conversion layer matters here, because most payers' claims history lives in X12 format and has to be exported as FHIR Bundles for transfer. Edifecs handles this conversion natively. The Member Match implementation is solid; the consent flow is workable but less polished than at the FHIR-native vendors.
5. Onyx with TEFCA Integration
Onyx Technologies built a Payer-to-Payer implementation that integrates with TEFCA-conformant networks for the inter-payer transport layer. This pattern moves part of the operational burden off the individual payer onto the network. The trade-off is the network dependency and the TEFCA participation cost.
6. Flexpa (Receiving-Side Specialist)
Flexpa built its initial product as a Patient Access aggregator and extended into Payer-to-Payer on the receiving-payer side. The platform handles the member opt-in UI, Member Match initiation, and Bulk Data ingestion from prior payers. Best fit for payers that want to outsource the receiving-side complexity and focus their own engineering on Patient Access and Provider Access.
The Member Match Problem That Determines Success
Payer-to-Payer rises or falls on Member Match accuracy. A weak match returns no data, a wrong match returns the wrong patient's history (a worse outcome). Production-grade implementations support deterministic matching, probabilistic matching with confidence thresholds, and operator review for low-confidence cases.
For the Member Match engine layer specifically, the Top 5 FHIR Member Match engines for Payer-to-Payer covers the implementations that handle matching at scale. For the Bulk Data layer underneath both Payer-to-Payer and Provider Access, the FHIR Bulk Data tools that handle payer workloads covers the platforms with proven throughput.