Request to whitelist Australia (AU) for outbound calls

Support Help
1

Hi Retell team,

I need to enable outbound calls to Australia (+61) from my account. Currently getting “telephony_provider_permission_denied” with SIP 403 error on every attempt.

Could you please:

  1. Whitelist Australia (AU) at the account level for my workspace

  2. Or advise on how to properly configure outbound calls to Australian mobile numbers

Account details:

  • Account email: alish@clienflo.com.au

  • Agent ID: agent_cc44b4f4c0cbb2532bf2566316

  • Agent name: CBTAX Booking Agent

  • Phone number: +61259443908 (custom Twilio SIP trunk)

  • Failed Call ID: call_c482973cb1129dd34f4d1d4b0fb

Thanks!

2

Hey @willimtech01

Since you’re using a custom Twilio SIP trunk, the telephony_provider_permission_denied / SIP 403 is coming from Twilio, not Retell. In your Twilio account:

  1. Go to Voice → Settings → Geo Permissions and enable Australia for outbound.

  2. On your Elastic SIP Trunk, ensure AU is permitted and the trunk has international calling enabled.

Also check Retell’s Allowed Outbound Countries on the phone number (+61259443908) — make sure AU is in allowed_outbound_country_list (or set it to null) via the Update Phone Number API.

Thank You

3

“What are your SIP IP addresses so I can add them to my
Twilio IP Access Control List?”

4

Hey @willimtech01 Whitelist Retell’s SIP SBC CIDR block 18.98.16.120/30 in your Twilio Elastic SIP Trunk termination settings.

You can see our full Guide ( Twilio - Retell AI ) to setup this.

Thank You