generated: '2026-08-13'
method: searched
source: https://postmarkapp.com/updates
docs:
  - https://postmarkapp.com/updates
  - https://status.postmarkapp.com
  - https://postmarkapp.com/terms-of-service
description: >-
  Versioning, deprecation and availability posture for the Postmark API. The
  headline finding is a mismatch: Postmark manages change responsibly in
  editorial practice — dated announcements, lead time, reminder posts — but
  publishes none of it as machine-readable policy, and the API itself carries no
  version handle a client could pin.
provider: Postmark
providerId: postmark

versioning:
  scheme: unversioned
  base_url: https://api.postmarkapp.com
  version_in_path: false
  version_in_header: false
  version_negotiation: false
  pinning_available: false
  note: >-
    No /v1 segment, no Postmark-Version header, no date-pinned versions. A
    change to the API applies to every caller at once.

deprecation_policy:
  published_policy_page: null
  rfc8594_headers: false
  sunset_header: false
  deprecation_header: false
  advance_notice: >-
    Observed in practice, not committed in writing. The HTTP removal was
    announced 2022-09-01 with a 2022-09-12 reminder; the static-IP allow-listing
    removal was announced 2023-07-18; the Email API validation tightening was
    announced 2023-10-31 with "Action may be required" in the title.
  note: >-
    Postmark publishes no deprecation policy document and emits no RFC 8594
    Deprecation or Sunset response headers. Notice reaches customers only
    through https://postmarkapp.com/updates and email. A
    `type: Deprecation` pointer IS emitted in apis.yml on the strength of the
    documented, dated deprecation announcements below — but readers should know
    it is editorial practice, not a stated policy with a guaranteed window.

deprecations:
  - date: '2023-07-18'
    subject: Static IP allow-listing for the API
    status: removed
    source: https://postmarkapp.com/updates
    impact: >-
      Customers who restricted API egress to Postmark's published static IPs had
      to stop relying on that control.
  - date: '2022-09-01'
    subject: API requests over plain HTTP
    status: removed
    source: https://postmarkapp.com/updates
    impact: All API traffic must be HTTPS. Reminder announcement posted 2022-09-12.
  - date: '2023-10-31'
    subject: Loosely-validated Email API request bodies
    status: tightened
    source: https://postmarkapp.com/updates
    impact: >-
      Requests that previously passed validation began returning ErrorCode 403
      (Invalid request field(s)). Postmark's error reference still links to this
      announcement from the ErrorCode 403 entry.

deprecated_operations_in_openapi: []
deprecated_operations_note: >-
  Zero operations across the 47 files in openapi/ carry `deprecated: true`.
  Consistent with an unversioned API that removes capability by announcement
  rather than by marking it in the contract.

status_page:
  url: https://status.postmarkapp.com
  status: 200
  probed: '2026-08-13'
  provider: Sorry™
  since: '2023-02-20'
  machine_readable_api: false
  note: >-
    A Status API was announced 2023-02-20. The Statuspage-convention endpoint
    https://status.postmarkapp.com/api/v2/status.json returns HTML rather than
    JSON (probed 2026-08-13), because the page is not Atlassian Statuspage — it
    is Sorry™. The page itself also publishes Postmark's delivery statistics to
    the major inbox providers, which is unusually transparent for the category.

sla:
  published_uptime_sla: null
  note: >-
    No numeric uptime SLA is published on the pricing page or the security page.
    Enterprise terms are handled through https://postmarkapp.com/talk-to-sales.

data_retention:
  default_days: 45
  scope: Full message content and activity history
  configurable_range_days: '7 to 365'
  add_on: Custom activity retention, from $5/month, Pro tier and above
  statistics: Retained indefinitely
  source: https://postmarkapp.com/pricing

data_removal:
  api: true
  since: '2023-12-08'
  operations:
    - Create a Data Removal request
    - Check a Data Removal request status
  source: https://postmarkapp.com/developer/api/overview

support:
  support_center: https://postmarkapp.com/support
  contact: https://postmarkapp.com/contact
  sales: https://postmarkapp.com/talk-to-sales