When an emergency call is initiated from a Webex Calling device or Webex App, the system first checks if the ELIN usage is allowed for that caller and device. If allowed, the system selects an available ELIN from the pool of numbers assigned to the caller’s location. This ELIN is temporarily assigned to the emergency event. It ensures that a unique, traceable number is linked to the caller. Emergency services can then call back the correct individual.

The ELIN remains assigned to the emergency caller for a configurable period, known as the ELIN expiry time. You can set this duration at the location level, anywhere from 10 to 1440 minutes, with a default of 60 minutes.

While the emergency call is active, the system resets the ELIN expiry timer every 5 minutes and again at the end of the call. This means the ELIN assignment duration always starts from the most recent refresh, so the ELIN stays available for callback for the full configured period after the emergency call ends.

Webex Calling uses the following process to assign and route emergency calls using ELINs, ensuring fast and accurate callbacks from emergency services.

• Emergency call initiation—A user dials an emergency number. For example, 911, 999, or 112.
• ELIN validation—The system checks if the user or workspace is eligible to use an ELIN and if one is available.
• ELIN assignment—If allowed and available, an ELIN is dynamically assigned to the caller for the duration of the emergency event.
• Call routing—The emergency call is sent to the Public Safety Answering Point (PSAP) with the assigned ELIN as the callback number and the correct ESA.
• Callback handling—If the PSAP calls back the assigned ELIN while it’s still active, the callback is immediately routed to the user or workspace assigned to the ELIN.
  • Webex Calling temporarily disables call forwarding, voicemail, and similar services for the emergency callback to ensure the call reaches the intended recipient without diversion.
  • If emergency call recording is enabled, it also applies to the callback.
  • The callback doesn’t affect the ELIN assignment duration. The ELIN remains assigned until its expiry time.
  • If the callback arrives after the ELIN assignment has expired, see the ELIN fallback mechanism section in this article.

Webex Calling ensures that an emergency callback number is always available, even if an ELIN isn’t available or is no longer assigned.

• No ELINs configured or available—If no ELIN is available, the system uses the configured ECBN for the user, workspace, or location.
• ELIN usage not allowed—If ELIN isn’t permitted for the caller or device, the system uses the ECBN directly.
• Workspace fallback—If a workspace is configured to use its own number as a callback (workspace number as ELIN) and no ELIN is available, the workspace number is used as the callback number.

  If ELINs are available in the location’s pool, the system uses an ELIN from the pool for emergency calls. The workspace number is used only if no ELINs are available. ELIN pool usage takes precedence over using the workspace number as ELIN.

• Callback to an expired ELIN—If emergency services call back an ELIN that is no longer assigned (expired), the system checks for an assigned ECBN at the location:
  • If the ECBN is assigned, the callback is routed to the designated entity (such as a reception desk or emergency contact). If the call is marked as an emergency callback, service inhibition and emergency call recording apply.
  • If the ECBN is unassigned or not configured, the call is rejected with a "User Not Found" message.
• Internal calls or redirection to ELINs—ELINs are reserved for external emergency callbacks only. Internal calls or redirections within the organization to an ELIN aren’t supported and are rejected with a "User Not Found" message.
• Webex Meetings and click-to-call—Calls made within Webex Meetings or via click-to-call aren’t routed to ELINs, including any ECBN fallback scenarios.
• Emergency test calls—Emergency test calls (933) use an ELIN when available, but don’t create an assignment.

ELINs are dynamically used for emergency calls based on several conditions related to the caller’s device, location, and administrative settings. We recommend that you consider the following scenarios to understand when and how ELINs are assigned.