How can I block unwanted calls (Blocklisting)?

Tired of telemarketing calls? Or do you have specific phone numbers you don't want to receive calls from? Then the Blocklist is the feature for you. 

Important: The voicemail feature must be booked and activated for the blocklist to work. Alternatively, you can book sipgate.io to enable call blocking.

Adding Numbers to the Blocklist

  • Click on My Telephony, then go to Settings in the left menu.
  • Select Blocklist and click Add Number to Blocklist.
  • A pop-up window will appear where you can enter a phone number. You can either block an exact number or block all numbers starting with the same digits.
  • Click Save to confirm.

Once added, all users on the account will see the blocked numbers in the blocklist settings. The blocklist applies to all users on the account, and any user can view, edit, or remove blocked numbers.

Unblocking Numbers

To remove a number from the blocklist

    • Click on the three dots next to the blocked number and select Delete. Calls from that number will now ring again.
    • The three-dot menu also allows you to edit a blocklisted number. 

Note: Your phone or device may have additional call-blocking or screening options.

Blocking Anonymous Calls

You can block calls with no caller ID or withheld numbers

  • Go to Personal Settings > Connections.
  • Select the connection you want to configure.
  • Scroll down and toggle Reject Anonymous Calls on.
  • Click the cogwheel icon to choose whether to block these calls completely or send them directly to voicemail.
  • Repeat for all connections if necessary.

For Groups, each user must update their settings individually.

Blocking Unwanted Direct IP Calls (SPIT)

Are you receiving direct IP calls from numbers like 100, 1001, or unknown IP addresses?

Many VoIP phones allow direct IP dialing, meaning a VoIP phone can call another directly via its IP address, bypassing sipgate's network. Unwanted direct IP calls are known as SPIT (Spam over Internet Telephony).
These calls do not go through sipgate's network, so they must be blocked locally on your VoIP device or router.

How to Stop SPIT Calls

  • Change your SIP login & password
  • Update firmware on your VoIP phone, router, and other connected devices
  • Check for malware on your computers and smartphones
  • Use a non-default SIP port (e.g., 44160 instead of 5060)

Most modern VoIP phones allow you to disable direct IP calls in the settings.

Device-Specific Blocking Methods

  • Grandstream Desk Phones

    • Go to Settings → Advanced Settings → Enable Disable Direct IP Calls
    • Under SIP Account Settings, enable Check SIP User ID for Incoming INVITE
    • In SIP Security Settings, set Accept Incoming SIP from Proxy Only to Yes

  • Snom Desk Phones (Firmware v8 and above):

    • Go to Advanced Settings → QoS/Security
    • Set Filter Packets from Registrar to Yes

Router Firewall Protection

If your router supports firewall rules, limit VoIP traffic to sipgate’s IP ranges for added security.
Since SPIT calls are a local network issue, your IT administrator or your VoIP device/router manufacturer’s support team can provide the best assistance.

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