Overview
Selective Call Rejection allows you to block incoming calls from specific phone numbers on your CT Cloud SIP trunk. Once a number is added to the rejection list, calls from that number will not reach your PBX.
Note: For SIP trunks, Selective Call Rejection applies trunk-wide — it blocks the listed number(s) across the entire trunk, not just a single line or extension.
Before You Begin
- You will need administrator access to CallTower Connect.
- Have the phone number(s) you want to block ready. Enter 10-digit numbers for US/Canada callers, or the full number as it appears on your Caller ID for international callers.
How to Add a Number to Selective Call Rejection
- Log in to CallTower Connect.
- Navigate to Menu > SIP Trunk > CT Cloud SIP (Meta).
- Locate the trunk you want to update and select it.
- Select Call Rejection.
- Select the + icon to add a new number.
- Enter the number you want to block.
- Select Save.
The number will now be rejected for all calls coming into the trunk.
Removing a Number from Selective Call Rejection
- Log in to CallTower Connect.
- Navigate to Menu > SIP Trunk > CT Cloud SIP (Meta).
- Locate the trunk and select Call Rejection.
- Find the number you want to remove from the list.
- Select the option to remove it, then select Save.
Limits
- Numbers must be no longer than 20 characters.
- A number may start with an asterisk, but all other characters must be digits.
- Up to 10 numbers may be added per trunk.
Related Articles
- CT Cloud SIP - User Portal For Trunks
- CT Cloud SIP - Applying Forwards on SIP Trunks in Connect
Need Help?
If you need further assistance, contact CallTower Support at (800) 347-5444 or support@calltower.com.

