Frequently asked questions about incoming call caller ID name (CNAM) display

Zoom Phone displays caller ID name (CNAM) information on incoming PSTN calls to help you identify who's calling. This article answers common questions about how CNAM is resolved and displayed, including recent improvements to replace generic labels with more useful information.

For more information about how Zoom Phone handles caller ID for both inbound and outbound calls, see Frequently asked questions about caller ID.

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Frequently asked questions about incoming call caller ID name (CNAM) display

What is CNAM and why does it matter?

CNAM stands for caller ID name. This is the name or label displayed on your screen when you receive an incoming call. Zoom Phone uses several data sources to resolve the best available name for each call. When no name is available, the display falls back to the caller's phone number or, if that's unavailable, "Unknown."

What displays now instead of "Wireless Caller," "Verified," or "Location"?

Zoom Phone now shows the caller's public switched telephone network (PSTN) phone number in place of those three generic labels. This applies on both the incoming call notification screen and the during-call screen across all supported platforms, including desktop (macOS, Windows, Linux, virtual desktop infrastructure), mobile (iOS, iPadOS, Android), Progressive Web App (PWA), Zoom Phone Appliances (ZPA), and desk phones.

Note: If both the CNAM and the caller's phone number are unavailable, the display falls back to "Unknown," which is consistent with existing behavior. For information on how inbound call notifications appear in the Zoom app, see Viewing inbound call notifications.

Does this change affect the STIR/SHAKEN caller verification checkmark?

No. The STIR/SHAKEN verification checkmark icon continues to display independently of the CNAM label. Replacing a generic label with the caller's phone number doesn't affect whether the verification checkmark appears.

What displays when I receive an internal call from a colleague?

For internal extension-to-extension calls, the caller's name and extension number from the company directory are displayed.

Note: If the calling extension doesn't have a name set in the company directory, only the extension number is displayed.

How does Zoom Phone decide which name to show when multiple sources have information about the caller?

Zoom Phone uses a fixed priority order to resolve the best available caller name for incoming PSTN calls. The client checks each source in the following order and displays the name from the highest-priority source that has a match:

  1. VIP contact
  2. Personal contact
  3. Cloud contact or connected account
  4. External contact or imported contacts
  5. Azure Active Directory (AAD) contact (third-party lookup)
  6. Phone contact matching (mobile)
  7. Zoom Phone contact (Zoom Contact Center, Zoom Virtual Agent, etc.) — extension name
  8. Third-party CNAM

This priority order is fixed and applies to all incoming external calls. It can't be changed by admins or users.

Can admins configure or change the CNAM priority order?

No. The CNAM priority order is a fixed platform behavior and isn't configurable in the admin portal or by individual users. It's documented here so admins can reference it when diagnosing caller ID display issues or explaining behavior to their users.

Will these changes affect call log records?

No. These improvements only affect what's displayed on the incoming call screen and during-call screen. Call log records are not modified.

Note: For incoming PSTN calls, it's possible that the display name is different from the call log. Call log records will be enhanced in the future.

Do these changes apply to all Zoom Phone accounts?

These improvements apply to all Zoom Phone accounts that have the Manage Caller ID operator flag (OP flag) enabled. No new OP flag is required. There are no geographic restrictions as these changes apply globally, including Zoom for Government (ZfG) and Zoom for Defense (ZfD) environments.

Will other existing CNAM labels like "Unknown" or "Anonymous" be affected?

No. Only the following three specific labels are replaced with the caller's phone number: "Wireless Caller," "Verified," and "Location". All other existing CNAM display behaviors, including "Unknown" and "Anonymous," remain unchanged.