united-yellow•2h ago
Outbound Call Failure: 403 Forbidden on Registered BYO SIP Trunk
My BYO SIP Trunk is registered and incoming calls to my Vapi number work perfectly. However, all outbound calls fail immediately with the following error in the logs:
call.in-progress.error-providerfault-outbound-sip-403-forbidden
Key Evidence:
Call ID:6c67c3b2-1dc0-4ac8-9f96-7a0a0762f78d, 32ad8386-3caf-4c77-9616-8e883c82ffa8, 21c5e36e-efaf-4f45-8ea1-7cc8e42d5627
SIP Provider: PBX HOSTING
Request:
Since inbound calls work, the issue appears to be with outbound authentication/authorization on my provider's side. Please:
Check your SIP logs for the Call ID above to see why the INVITE is being rejected.
Provide the public IP addresses Vapi uses for outbound SIP traffic so I can whitelist them with my provider.
Thank you for your assistance.
1 Reply
To allow outbound SIP traffic from Vapi, please whitelist the following public IP addresses with your provider:
Ensure these IPs are allowed for SIP signaling and media. This should help resolve outbound call authorization issues if IP whitelisting is required by your provider.
See Vapi SIP trunk documentation for details. Source: - Vapi SIP Trunk Documentation
See Vapi SIP trunk documentation for details. Source: - Vapi SIP Trunk Documentation
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