Overview of blocklist

You can create a block list for your organization and add numbers from specific callers to reject.

Here are few benefits with this feature:

  • Webex Calling customer administrators can block incoming PSTN calls from numbers which are either spam or harassing. You can configure policies for an organization to block calls from configured numbers (for example telemarketing callers, collection agencies) or known offenders (such as disgruntled customers or exemployees). Blocking these calls reduce wasted time, and protect the users from security threats or harassment.

  • You can make an outbound call to the blocked numbers and generate a CDR report.

Create a block list

Configure a block list with numbers that can’t make incoming calls to your organization.


From the administrator view in https://admin.webex.com, go to Services > Calling.


Go to Service settings and scroll down to Call Block List.

You can add or remove phone numbers, country codes, or other patterns to the call block list.

  • Block calls with no caller ID—This option blocks incoming calls from PSTN without calling line information (Caller ID).

  • Block calls from hidden private numbers—This option blocks all calls from callers with private numbers or hidden identities.


Select Add to add numbers or patterns to block from calling the user's organization. The Add numbers to call block list window displays.

Follow these guidelines for adding numbers or patterns:

  • Enter patterns in E164 format.

  • Wildcards include the use of ! which represents a sequence of one or more digits.

  • X represents a single number (0-9).

You can add up to 200 numbers or patterns per organization. To add numbers in bulk, select Import CSV.

Numbers and patterns added to the block list is visible above the input field. Each number is validated as they are entered.

When you don’t enter any blocked numbers, a notification stating that there are no current blocked numbers added to this customer organization displays.


Click Save, to save the number. To remove a number, select X. Save is enabled after entering the first valid number.

A list with all the blocked numbers displays. Click Delete, to delete an entry or use Clear all, to delete all numbers in the block list. A notification displays to confirm the action.