generated: '2026-08-14'
method: searched
source: >-
  https://mailosaur.com/pricing,
  https://mailosaur.com/docs/managing-your-account/usage-limits,
  https://mailosaur.com/docs/inboxes/usage-limits, https://mailosaur.com/docs/api,
  plus a live unauthenticated probe of https://mailosaur.com/api/servers (2026-08-14)
limit_count: 5
response_headers:
  headers: []
  status_on_exhaustion: null
  probed:
    url: https://mailosaur.com/api/servers
    fetched: '2026-08-14'
    http_status: 401
    observed_headers:
      - 'date'
      - 'cache-control: no-store, must-revalidate, no-cache'
      - 'www-authenticate: Bearer'
      - 'strict-transport-security: max-age=31536000; includeSubdomains; preload'
      - 'x-frame-options: SAMEORIGIN'
      - 'x-content-type-options: nosniff'
  note: >-
    Mailosaur returns NO runtime rate-limit signal. No X-RateLimit-*,
    RateLimit-* or Retry-After header is documented, and none appears on a live
    response. There is no documented HTTP status for exhaustion either: per
    https://mailosaur.com/docs/managing-your-account/usage-limits, exceeding the
    daily email allowance causes inbound email to be REJECTED at the mail layer
    and SMS to stop being processed — neither of which the API caller ever sees.
    Per https://mailosaur.com/docs/inboxes/usage-limits, an inbox over its
    monthly inbound SMS limit SILENTLY DROPS further messages, while an
    over-limit outbound SMS send returns a validation error. The only
    programmatic signal available to an agent is polling GET /api/usage/limits
    (getUsageLimits), which returns current limits and consumption for servers,
    users, email and SMS.
reset_schedule:
  daily: midnight UTC each day
  monthly: midnight UTC on the 1st of each calendar month
metered_dimensions:
  - Email (daily; received and sent combined)
  - SMS (monthly; received and sent counted separately)
  - Email previews (monthly)
  - Screenshots (monthly; one per client/device per preview)
resource_quotas:
  - Inboxes (servers)
  - Users
  - Phone numbers
inbox_level_limits:
  available_on: Enterprise
  note: >-
    Enterprise accounts can cap an individual inbox's daily email, monthly
    inbound SMS and monthly outbound SMS, so one team cannot consume the whole
    account allowance. A message is rejected when it exceeds either the account
    limit or the inbox limit, whichever is reached first.
specificationVersion: "0.1"
id: mailosaur-rate-limits
name: Mailosaur Rate Limits
description: >-
  Mailosaur enforces inbound email volume limits per plan rather than
  per-request HTTP rate limits on the REST API. Daily and monthly inbound
  email caps vary by plan. The API itself does not publish explicit
  per-second or per-minute request throttle limits in its documentation.
url: https://mailosaur.com/docs/api
rateLimits:
  - name: Personal Plan — Monthly Email Cap
    description: Maximum inbound emails received per calendar month on the Personal plan.
    scope: account
    limit: 15000
    unit: emails
    window: month
    planApplicability:
      - Personal

  - name: Personal Plan — Daily Email Cap
    description: Maximum inbound emails received per day on the Personal plan.
    scope: account
    limit: 500
    unit: emails
    window: day
    planApplicability:
      - Personal

  - name: Core Plan — Monthly Email Cap
    description: Maximum inbound emails received per calendar month on the Core plan.
    scope: account
    limit: 75000
    unit: emails
    window: month
    planApplicability:
      - Core

  - name: Core Plan — Daily Email Cap
    description: Maximum inbound emails received per day on the Core plan.
    scope: account
    limit: 2500
    unit: emails
    window: day
    planApplicability:
      - Core

  - name: Enterprise Plan — Custom Caps
    description: >-
      Email volume limits are negotiated as part of the Enterprise plan
      contract. Contact Mailosaur sales for details.
    scope: account
    limit: null
    unit: emails
    window: custom
    planApplicability:
      - Enterprise

notes:
  - >-
    Mailosaur's public documentation does not specify HTTP request rate limits
    (requests per second/minute) for the REST API. Developers hitting usage
    limits will receive 429 or account-limit error responses.
  - >-
    The account usage endpoint (GET /api/usage/limits) can be queried
    programmatically to retrieve current plan limits and consumption figures.
  - >-
    SMTP inbound is available on ports 25, 2525, and 587; POP3 on ports 110
    and 995. These protocol endpoints are not subject to separate published
    rate limits.