specification: API Commons Rate Limits
specificationVersion: '0.1'
schema: https://raw.githubusercontent.com/api-evangelist/interface-research/main/schema/api-commons.yml#/$defs/RateLimits
provider: GP Connect (NHS England)
providerId: gp-connect
created: '2026-06-13'
modified: '2026-06-13'
reconciled: false
tags:
  - NHS
  - FHIR
  - Healthcare
  - Rate Limiting
  - UK
description: >
  NHS England does not publish explicit per-endpoint rate-limit headers for
  the GP Connect APIs. Access is mediated by the Spine Security Proxy (SSP)
  for clinical system APIs (Access Record Structured, Access Document,
  Appointment Management, Send Document, Update Record) and by NHS login
  OAuth 2.0 token scopes for patient-facing APIs. Fair-use constraints apply
  at the SSP and Spine layer. Production capacity is governed by NHS England
  infrastructure rather than per-API-key quotas.
sources:
  - https://developer.nhs.uk/apis/gpconnect-1-0-0/development_fhir_api_guidance.html
  - https://digital.nhs.uk/developer/api-catalogue/gp-connect-access-record-structured-fhir
  - https://digital.nhs.uk/developer/guides-and-documentation/reference-guide#service-levels
algorithm: spine-proxy-fair-use
responseCodes:
  throttled: 429
  quotaExceeded: 429
notes: >
  The Spine Security Proxy (SSP) acts as a single-entry TLS mutual
  authentication point for all clinical GP Connect APIs. There are no
  published X-RateLimit-* response headers. HTTP 429 may be returned under
  extreme load. Service level is Silver (24x7 availability, business-hours
  support Mon-Fri 08:00-18:00 excl. bank holidays).
limits:
  - id: sandbox-open-access
    scope: environment
    label: Sandbox environment rate limit
    value: -1
    notes: >
      Sandbox is open access and stateless. No hard rate limit is published;
      fair-use expected. Sandbox does not reflect production throughput.
  - id: service-level-silver
    scope: platform
    label: Service level (Silver)
    value: 99.9
    unit: percent-uptime
    notes: >
      Silver service: 24/7 availability, business-hours support only
      (Mon-Fri 08:00-18:00 excl. bank holidays). Applies to all GP Connect
      integration and production environments.
  - id: ssp-connection-limit
    scope: system
    label: SSP concurrent connections
    value: -1
    notes: >
      Limits governed at the HSCN/SSP infrastructure level. Consuming
      systems must be SSP-compliant and hold valid Spine credentials.
      No per-system numeric cap is publicly documented.