HL7 FHIR

When it applies

FHIR applies wherever clinical or administrative data is exchanged between systems at the application level — between an EHR and a portal, between a hospital and a jurisdictional registry, between a lab and a clinician-facing form. It is the current base standard for new integrations in Australia, New Zealand, and the United States, and is displacing HL7 v2 messaging for new build since the mid-2020s. FHIR R4 is the interoperable baseline across jurisdictions; FHIR R5 adds subscription topics and ecosystem refinements but has slower regulatory uptake.

How it differs across Australia, New Zealand, and the United States

Australia uses AU Core profiles governed by HL7 Australia under the Sparked programme, with national adoption coordinated by the Australian Digital Health Agency (ADHA). New Zealand uses NZ Base profiles governed by HL7 New Zealand and referenced by HISO standards and the Hira programme. The United States uses US Core profiles, which the ONC mandates through HTI-1 and which underpin TEFCA exchange and USCDI data classes. The resources are identical at the base level; the jurisdictional profiles constrain must-support elements, value sets, and extensions.

Common misconceptions

FHIR is not a replacement for HL7 v2 overnight. Most jurisdictions run both for 10+ years, migrating domain-by-domain rather than via single cutover. FHIR is not REST-only — the standard supports messaging, documents, and subscription-based delivery. FHIR alone does not guarantee interoperability — profiling, terminology binding (SNOMED CT, LOINC), and implementation guide discipline do.

Related terms

• HL7 v2
• SMART on FHIR
• USCDI
• TEFCA
• AU Core, NZ Base, US Core (profile families)