When attempting to make outbound calls in LiveAgent using Twilio as your VoIP provider, you may encounter a "Call Rejected" error. This article explains the most common cause of this error and how to resolve it by allowlisting LiveAgent's call center IP addresses in Twilio.
Why Does This Error Occur?
Twilio and other SIP trunk providers allow you to restrict which IP addresses can communicate with your trunk. If LiveAgent's call center (SIP) server IP addresses are not added to Twilio's allowed IP list, outbound — and potentially inbound — calls will be rejected with the "Call Rejected" message.
How to Fix It
Step 1: Obtain the LiveAgent IP Addresses
The current and complete list of LiveAgent server IP addresses — including both application server IPs and call center (SIP) IPs — is available in the following support article:
LiveAgent Servers IP Addresses
An older article about SIP/call center IP addresses (previously located at /856936-List-of-IP-addresses-used-by-SIPcall-center) is no longer available. Please use the updated link above for the current list of IP addresses.
Step 2: Add the IPs to Twilio's Allowed IP List
- Log in to your Twilio Console.
- Navigate to SIP Trunk > IP Access Control List for your trunk.
- Add each of the LiveAgent call center (SIP) IP addresses from the article above to the allowed/whitelisted IPs.
- Save your changes.
Step 3: Test the Outbound Call
After updating the IP allowlist in Twilio, attempt the outbound call again from LiveAgent. The "Call Rejected" error should be resolved.
Important Notes
- LiveAgent IP addresses are fixed and do not change dynamically.
- The LiveAgent IP address article covers both application server IPs (used for general connectivity) and call center/SIP IPs (required for VoIP calls). Make sure to allowlist the call center IPs specifically.
- If you are using a different SIP/VoIP provider (not Twilio), the same principle applies — add LiveAgent's call center IPs to that provider's IP allowlist.
Still Having Issues?
If the problem persists after allowlisting the IP addresses, contact the LiveAgent support team and provide the following information:
- Your LiveAgent account domain (e.g., yourcompany.ladesk.com)
- The date and time the issue occurred
- Any relevant call records or error logs
LiveAgent support can investigate backend logs to identify any additional configuration issues with your VoIP setup.
Resolving "Call Rejected" Errors for Outbound Calls in LiveAgent with Twilio by Allowlisting IP Addresses