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Notice: Telstra Australian Caller ID Restrictions - Reducing Scam Calls Industry Code (November 2021)

By the end of March 2022, Telstra is slated to begin implementing restrictions on Caller IDs terminating to their network in order to reduce scam calls. To maintain service continuity, all Twilio users calling to Telstra Australian destinations will need to call from Twilio Phone Numbers.

This guide covers the following topics:

UPDATE - November 2021: Telstra terminating caller ID restrictions in Australia have been delayed until March 2022. The previous timeframe was November 2021.

Why are the Caller ID rules changing?

The Australian Communications Alliance is implementing the Reducing Scam Calls Industry Code (C661:2020) in order to identify, track, block and disrupt scam calls. 

According to Section 4.2.1 of the Industry Code, a telecommunications operator can only originate calls on its network with Caller IDs using the Phone Numbers it has been allocated. 

If you make calls to Australian Phone Numbers on the Twilio network, using Phone Numbers not assigned to you by Twilio, the calls might be blocked by Australian operators.

Which calls will be impacted by Telstra’s implementation of this regulation?

In March 2022, Telstra will start blocking calls from Twilio originating on networks in Australia that have:

  1. Outgoing and Verified Caller-ID Phone Number: Telstra Phone Number (rather than a Twilio Phone Number) 
  2. To Phone Number: Telstra Phone Number 

This restriction only applies to calls from Telstra-held Australian Caller IDs to Australian Phone Numbers. If you use Twilio Phone Numbers for making calls to Australian Phone Numbers, those calls won’t be affected.

Other operators in Australia may also begin implementing the Industry Code in the coming months. Twilio will keep you updated as we learn more.

What do you need to do?

  1. To continue making calls using the Telstra-held Australian Caller IDs that you have as Caller IDs with Twilio, port your Phone Numbers from Telstra to Twilio. You can find more information about how to port a Phone Number here. Please review the Porting guidelines for Australia to understand restrictions and best practices. Porting Phone Numbers usually takes 4-6 weeks. 
  2. To use a Twilio Outgoing/Verified Caller ID to enable a callback from users, you can use a Twilio Phone Number for making outbound calls and then use call-forwarding for receiving inbound calls, by following these steps:
    • Submit the information outlined in Regulatory Requirements for Australia to get a new Twilio Phone Number. Please follow the process outlined here for submitting the required regulatory information through the Twilio Console for approval.
    • Once the regulatory information is approved, you can get a new Phone Number via the Twilio Console or the Twilio API. It will take approximately 2-3 weeks to receive the new Phone Number.
    • In order to redirect your inbound calls to your desired Phone Number, you can enable call-forwarding on your new Twilio Phone Number by following these steps.

(Additional update) If you need to make calls while keeping the Phone Numbers private, you can use the Twilio Proxy API for voice conversations between users. To implement Proxy, review our Twilio Proxy Quickstart, or following these steps:

  1. Get a new Phone Number(s) via the Twilio Console or the Twilio API, with the regulatory information approved.
  2. Gather your account information.
  3. Set up your development environment.
  4. Create a Proxy service.
  5. Add Phone Number(s) to your service.
  6. Create a session.
  7. Create participants.
  8. Make a voice call.

Additional resources

To set up  your Caller ID when originating calls from Twilio, refer to these support articles: 

For information on provisioning phone numbers from Twilio:

For information on Australian Regulatory Guidelines:

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