Greenway Health API integration guide: Intergy, Prime Suite, FHIR and GAPI

The short answer

Greenway publishes read-only FHIR R4 docs with no login, and lets developers register and submit SMART on FHIR apps to its App Gallery after review. Read-write work goes through GAPI, Greenway's proprietary API, available to Marketplace partners and clients; its terms and fees aren't public.

The flavors to tell apart

• Intergy. EHR and practice management.
• Prime Suite. EHR and practice management, Greenway's other ambulatory line.
• Patient Portal and SmartHub. Patient-facing products where FHIR and SMART can be activated.
• Version gates. Greenway lists minimum product versions for FHIR and SMART, and the minimum moves each year. Practices check theirs on MyGreenway.

How access works

1. Register on the developer platform.
2. Create your SMART app: description, audience, launch type (standalone, EHR-embedded or backend), auth and scopes. PKCE is mandatory.
3. Switch to production and submit. Greenway reviews technical details and documentation; approved apps appear in the App Gallery.
4. Practices opt in to FHIR services themselves.
5. For GAPI, work through Greenway's Marketplace partner process.

What the APIs cover

Our take

FHIR on Greenway gets you reading quickly. Anything operational means a GAPI conversation, so open it early, and check each practice's product and version before you promise a go-live date.

FAQ

Does Greenway Health have a FHIR API?

Yes, a read-only FHIR R4 API with public documentation and a SMART on FHIR App Gallery.

What is Greenway GAPI?

Greenway's proprietary API for reading and writing clinical and financial data, available to Marketplace partners and clients.

Do all Greenway practices support FHIR?

They need a supported product version and must opt in. Greenway publishes minimum version requirements that change annually.

Sources

Public pages, accessed 11 Oct 2026: Greenway API overview · Create and publish SMART on FHIR apps · Minimum product requirements · Greenway on AWS HealthLake