### Answer To add a Brazilian number to Retell AI, you'll use Elastic SIP Trunking to connect your existing number from a telephony provider [(1) ]() . This is the recommended integration method that allows you to use your own phone numbers with Retell AI [(1) ]() [(2) ]() . ## Setup Process 1. Set up SIP trunking with your telephony provider (like Twilio, Telnyx, or Vonage) and configure your Brazilian number to point to it [(1) ]() 2. Configure the SIP trunk to connect to Retell's SIP server:

sip:sip.retellai.com

3. Import your number into Retell AI by providing the termination URI from your SIP trunk provider [(1) ]() [(3) ]() When importing, you'll need to supply your provider's termination SIP URI, along with username and password for authentication [(3) ]() . Once imported, your Brazilian number will function just like a Retell-purchased number—it will appear in your dashboard and support all telephony features that your provider supports [(1) ]() . ## Latency Performance Retell AI typically achieves sub-800ms end-to-end latency [(4) ]() . You can monitor latency metrics through the dashboard or via the Get Call API . The latency breakdown includes : - **End-to-end (e2e) **: Total time from when the user stops speaking until the AI agent begins responding - **ASR**: Transcription latency - **LLM**: LLM processing time - **TTS**: Text-to-speech conversion time Each metric pr

ovides statistical data including p50, p90, p95, p99, min, max values . The SIP trunking method maintains the same latency performance as Retell's native numbers, assuming your telephony provider supports the required features [(1) ]() .

​ To learn more, see the sources I considered: [[1] Custom Telephony Overview](https://docs.retellai.com/deploy/custom-telephony) [[2] AI in SIP Calling & Telephony Solutions | Retell AI](https://www.retellai.com/blog/integrating-ai-with-sip-trunking-and-modern-telephony) [[3] Telnyx](https://docs.retellai.com/deploy/telnyx) [[4] Check actual latency](https://docs.retellai.com/reliability/check-actual-latency) ​

Feel free to tag @AI Evy with additional questions. I also appreciate feedback, it helps me improve.