Account owners and admins can manage blocked numbers in the account. Blocked numbers can be incoming (numbers will be blocked from calling in and sending SMS) and outbound (phone users in your account won't be able to dial/text those numbers). You can also block all inbound calls that hide their caller ID. 

Admins can also block incoming external calls for Zoom Rooms and common area phones. For example, since Zoom Rooms and common area phones are often located in public area, you can block all external calls if the room or phone has a direct number and is receiving a lot of spam calls.

Phone users can also manage their own blocked list from the web portal or block a phone number directly from their Zoom app. 

This article covers:

• Limitations of the blocked list
• Effects of blocking calls
• How to block phone numbers, prefixes, or callers without a caller ID (account level)
  
  • Activate or deactivate blocked numbers
  • Delete blocked numbers
• How to block phone numbers, prefixes, or callers without a caller ID (phone user level)
  
  • Delete blocked numbers
• How to block external calls
  • Account
  • Site
  • Phone user, Zoom Room, or common area phone

Prerequisites for blocking calls on Zoom Phone

• Pro, Business, or Education account
• Account owner or admin privileges
• Zoom Phone license 

Limitations of the blocked list

• Blocking phone numbers, prefixes, or callers without a caller ID is available at the account or phone user level. If you have multiple sites, you can't apply block numbers for a specific site.
• Blocking external calls is available at the account, site, or extension (specific phone users, Zoom Rooms, common area phones) levels.
• Blocking external calls only applies to phone users, Zoom Rooms, and common area phones. For example, if you block external calls at the account, only these extensions in the account will be affected.
• Blocking external calls only applies to inbound calls and SMS, meaning outbound calls and SMS to external phone numbers will still be allowed.

Effects of blocking calls

• Blocked calls will not appear in the admin call log and associated phone user's call history.
• Blocked callers will hear a generic message stating that the person they are trying to reach is not available.
• If a phone user calls a blocked outbound phone number, they will hear the same generic message stating that the person they are trying to reach is not available.
• If you blocked numbers at the user level, they can view or change your blocked numbers in their phone settings.
• If you blocked numbers at the account level, phone users can only view (not change) your blocked numbers in their phone settings.

How to block phone numbers, prefixes, or callers without a caller ID (account level)

You can add block rules for all phone users in the account to block a specific number or all numbers with a prefix (country code and area code).

1. Sign in to the Zoom web portal.
2. In the navigation menu, click Phone System Management then Company Info.
3. At the top, click Account Settings.
4. Click the Blocked List tab.
5. Click Add.
6. Enter the following information:
   
   • Match Type
     • Select Prefix Match if you want to block all numbers with a specific country code and area code.
       Note: Enter a country code as part of the prefix. For example, entering 1905 blocks numbers with country code 1 and area code 905.
     • Select Phone Number Match if you want to block a specific phone number.
       Note: Enter a country code before the prefix or phone number. For example, entering 19051231234, blocks number +1 (905) 123-1234.
   • Type
     • Select Inbound to prevent the blocked number or prefix from calling/texting in to phone users.
     • Select Outbound to prevent phone users from calling the blocked number or prefix.
   • Comment (optional): Enter a comment to help you identify the blocked number or prefix.
   • Status: Enable or disable the blocked number.
7. Click Save.
8. (Optional) Click Account Management, Account settings, then click the Zoom Phone tab, to enable the Block Calls without Caller ID toggle to block all incoming callers that hide their caller ID.

Activate or deactivate blocked numbers

After adding numbers to the Blocked List, you can activate or deactivate them. Deactivated blocked numbers will appear but won't apply to any outbound or inbound calls until activated.

1. Sign in to the Zoom web portal.
2. In the navigation menu, click Phone System Management, then Company Info.
3. At the top, click Account Settings.
4. Click the Blocked List tab.
5. Click Edit next to the rule you want to activate or deactivate.
6. Switch the Status toggle on to activate the blocked number or switch it off to deactivate.
7. Click Save.

Delete a blocked number

You can delete numbers from your block list if you don't want to block that number. You can only delete numbers or rules one at a time.

1. Sign in to the Zoom web portal.
2. In the navigation menu, click Phone System Management, then Company Info.
3. At the top, click Account Settings.
4. Click the Blocked List tab.
5. In the last column, click Delete next to the rule you want to remove.
6. Click Delete to confirm.

How to block phone numbers, prefixes, or callers without a caller ID (phone user level)

Follow these steps if you only want block rules to apply to a specific user.

Note: Each phone user can view or change these blocked numbers in their phone settings. Block numbers applied to the entire account will still apply to the phone user if you set user-specific block rules.

1. Sign in to the Zoom web portal.
2. In the navigation menu, click Phone System Management, then Users & Rooms.
3. Click the name of the user you want to block numbers for.
   Note: You can only block numbers for phone users, not Zoom Rooms added to Zoom Phone.
4. Click User Settings.
5. Scroll down to the Blocked List section and customize these settings:
   • Click Manage Blocked List to block specific phone number or prefixes.
     Blocked prefixes and numbers that apply to all users are displayed beside Default.
     Click Add in one of the following sections to block prefixes, numbers, or extensions.
     • Blocked phone number prefixes: To the right of Blocked Prefixes, click Add to block all numbers with a specific country code and area code. Select an area code, enter a prefix, and click Save.
       For example, entering 1905 blocks numbers with country code 1 and area code 905.
     • Blocked numbers: To the right of Blocked Numbers, click Add to block a specific phone number. Select an area code, enter a phone number, and click Save.
       For example, entering 19051231234, blocks number +1 (905) 123-1234.
   • (Optional) To the right Block Calls without Caller ID, click the toggle to block all incoming callers that hide their caller ID.
   • To the right of Block External Calls, click the toggle to set rules for blocking incoming external calls during business, closed, and holiday hours.
     Note: This setting only applies to incoming calls. Phone users can still call external phone numbers.

Delete a blocked number

You can delete numbers from your block list if you don't want to block that number. You can only delete numbers or rules one at a time.

1. Sign in to the Zoom web portal.
2. In the navigation menu, click Phone System Management, then Users & Rooms.
3. Click the name of the user you want to block numbers for.
4. Click User Settings.
5. Next to Blocked List, click View or Edit.
6. Next to Blocked phone number prefixes or Blocked numbers, click × next to the blocked number or prefix you want to delete.

How to block external calls 

You can also block all inbound external calls for at the account, site, or extension (specific phone users, Zoom Rooms, common area phones) level. Blocking external calls only applies to inbound calls/sms, meaning outbound calls/sms to external phone numbers will still be allowed.

Note:

• Blocking external calls only applies to phone users, Zoom Rooms, and common area phones. If you block external calls at the account, only these extensions in the account will be affected.
• External calls includes all calls from phone numbers that are:

  • not direct Zoom Phone numbers in the same account,

  • not configured as part of BYOC, or

  • not synchronized from Exchange or Active Directory.

Account

1. Sign in to the Zoom web portal.
2. In the navigation menu, click Phone System Management, then Company Info.
3. Click Account Settings at the top.
4. Click the Settings tab.
5. Scroll down to the Others section.
6. Enable the Block External Calls toggle.
7. Change these settings:
   • Block hours: Select whether to apply the rule during affected extension's business, closed, or holiday hours.
   • When a call is blocked: Route blocked calls to the affected extension's voicemail, or immediately disconnect the call.
   • Apply changes to: Select whether to apply the rule to all existing sites/extensions or all new sites/extensions.

Site

1. Sign in to the Zoom web portal.
2. In the navigation menu, click Phone System Management, then Company Info.
3. Click the name of the site you want to edit, then click the Settings tab.
4. Scroll down to the Others section.
5. Enable the Block External Calls toggle.
6. Change these settings:
   • Block hours: Select whether to apply the rule during affected extension's business, closed, or holiday hours.
   • When a call is blocked: Route blocked calls to the affected extension's voicemail, or immediately disconnect the call.
   • Apply changes to: Select whether to apply the rule to all existing sites/extensions or all new sites/extensions.

Phone user, Zoom Room, or common area phone

1. Sign in to the Zoom web portal.
2. In the navigation menu, click Phone System Management, then Users & Rooms.
3. Click the Users, Zoom Rooms, or Common Area Phones tab depending on what extension you want to edit.
4. Click the name of the extension you want to edit.
5. Click the User Settings or Settings tab.
6. Scroll down to the Others section.
7. Enable the Block External Calls toggle.
8. Change these settings:
   • Block hours: Select whether to apply the rule during affected extension's business, closed, or holiday hours.
   • When a call is blocked: Route blocked calls to the affected extension's voicemail, or immediately disconnect the call.