I'm trying to configure a Twilio SIP Trunk using the "traditionnal SIP config" and it doesn't work. | ElevenLabs | Page 1

verbal condorBOT Jan 12, 2026, 10:09 AM

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AI-generated Answer for k0rvent

Short answer: your Twilio Origination URI is missing the required user/identifier. ElevenLabs’ SIP trunk only routes calls when the SIP URI includes an identifier (e.g., the E.164 number you imported). Update Twilio to something like:
sip:+15551234567@sip.rtc.elevenlabs.io:5061;transport=tls
Make sure the number format (with or without +) exactly matches how you imported it in ElevenLabs; mismatches will not route. (elevenlabs.io)

Checklist against ElevenLabs’ SIP trunking doc:

SIP destination: use sip.rtc.elevenlabs.io with port 5061 for TLS (or 5060 for TCP). UDP is not supported. (elevenlabs.io)
Identifier required: don’t send sip:sip.rtc.elevenlabs.io without a user part. Use sip:<identifier>@sip.rtc.elevenlabs.io:<port>. (elevenlabs.io)
ElevenLabs “Outbound Address” must be a hostname only (no sip: prefix). Your Address looks fine. (elevenlabs.io)
Media encryption: set to Allowed or Required if your carrier requires SRTP; Disabled will fail against trunks that mandate SRTP. TLS + Required media encryption is the recommended best practice. (elevenlabs.io)
Firewall/ports: allow SIP signaling to 5061 (TLS) or 5060 (TCP), and RTP UDP ranges for media. (elevenlabs.io)

About Twilio-side toggles: ElevenLabs docs do not require changing Twilio “Call Transfer/REFER” settings for SIP trunking to work. The critical Twilio item, per our docs, is the Origination URI with the correct identifier and transport/port. (elevenlabs.io)

If issues persist, test with:

TCP (port 5060) instead of TLS to isolate TLS/certificate problems, then re-enable TLS. (elevenlabs.io)
Media Encryption = Allowed before enforcing Required, to confirm SRTP interoperability. (elevenlabs.io)

References: ElevenLabs SIP trunking documentation. (elevenlabs.io)

tribal burrow Jan 12, 2026, 10:12 AM

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" ElevenLabs’ SIP trunk only routes calls when the SIP URI includes an identifier (e.g., the E.164 number you imported). Update Twilio to something like: sip:+15551234567@sip.rtc.elevenlabs.io:5061;transport=tls"

But Twilio should add it by itself we shouldn't have to hardcode the identifier in it right?

verbal condorBOT Jan 12, 2026, 10:12 AM

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AI-generated Answer for k0rvent

Short answer: No. For ElevenLabs SIP trunking to route the call, the Request-URI must include an identifier (typically the E.164 number you imported). Calls sent to sip.rtc.elevenlabs.io without a user part will not be routed by ElevenLabs. (elevenlabs.io)

What to change in Twilio:

Set your Twilio Origination URI to include the identifier, for example:
sip:+15551234567@sip.rtc.elevenlabs.io:5061;transport=tls
This satisfies the “identifier@domain:port” requirement on the ElevenLabs side. (elevenlabs.io)

Important details:

The identifier’s format must match how you imported the number (including whether it has a leading “+”). A mismatch will prevent routing. (elevenlabs.io)
Use port 5061 for TLS (5060 is for TCP). Ensure your SIP transport/encryption settings match. (elevenlabs.io)

Notes:

ElevenLabs does support Twilio’s sip.twilio.callSid header for metadata fallback, but this does not replace the need for an identifier in the SIP URI used for routing. (elevenlabs.io)

References:

ElevenLabs SIP trunking guide (identifier requirement, URI format, ports, number format matching). (elevenlabs.io)

tribal burrow Jan 12, 2026, 10:14 AM

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Isn't there a config/parameter in Twilio to automatically append the identifier to the Origination URI?

#I'm trying to configure a Twilio SIP Trunk using the "traditionnal SIP config" and it doesn't work.