​ To learn more, see the sources I considered: [[1] AI Phone Numbers: How to Buy & Set Up | Retell AI](https://www.retellai.com/blog/how-to-buy-an-ai-phone-number-a-guide-on-your-options-and-providers) [[2] How can I purchase a Colombian local number?](https://discord.com/channels/1186424376300679209/1304454700266946581) ​

### Answer Retell AI currently only supports US-based numbers for direct purchase through the platform. [(1) ]() [(2) ]() For Hong Kong and China local numbers, you would need to: 1. Use custom telephony — Purchase numbers from a third-party provider (like Twilio, Telnyx, or a local carrier) that offers numbers in those regions, then connect them to Retell AI via SIP trunking. [(2) ]() Check out this resource for setting up custom telephony: [Custom Telephony Documentation]()

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

### Answer Yes, a local carrier refers to a local telephony service provider in your region that provides phone numbers and voice services. [(1) ]() In the context of connecting numbers to Retell AI (like for Hong Kong or China) , you would: 1. Get telephony services from a local carrier in that country 2. Connect that carrier to Retell AI via SIP trunking For example, one community member mentioned connecting a local carrier in India to a service like Cloudonix, and then from there to Retell AI. Some users also work with VoIP providers that offer SIP trunking services in specific regions. [(2) ]() [(9) ]()

​ To learn more, see the sources I considered: [[1] Connect phone number](https://discord.com/channels/1186424376300679209/1371798273182011484) [[2] Local VOIP Provider not giving E.164 Format](https://discord.com/channels/1186424376300679209/1444865486499221588) ​

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

@AI Evy Does it mean I can buy a local number and it will work? I am confuse how to set up the local carrier. Any specific information I should have?

### Answer --- Buying a local number from a carrier is just the first step—you also need to connect it to Retell AI via SIP trunking. Here's what you need: What you need from your local carrier/VoIP provider: 1. A phone number in your target region (Hong Kong/China) [(1) ]() 2. SIP trunk credentials — typically includes: - Termination SIP URI (for outbound calls) [(2) ]() - Username and password for authentication - Origination settings pointing to Retell's SIP server:

sip:sip.retellai.com

(for inbound calls) Setup process: 1. Purchase the local number from your carrier [(1) ]() 2. Move/configure the number on an elastic SIP trunk with your provider [(2) ]() 3. Set up termination (outbound) with proper SIP URI and authentication 4. Set up origination (inbound) pointing to

sip:sip.retellai.com

5. Import the number to Retell via the dashboard or API, providing the termination SIP URI and credentials Important note: Your carrier must provide numbers in E.164 format (e.g.,

+852XXXXXXXX

for Hong Kong) . Some local providers may not do this by default, which can cause issues. [(3) ]() For detailed Twilio SIP trunk setup steps, see: [Twilio SIP Trunk Documentation]() [(2) ]()

​ To learn more, see the sources I considered: [[1] I need some help setting up international calls through Retell + Twilio.](https://discord.com/channels/1186424376300679209/1384814836902400070) [[2] I’m trying to use a toll-free number (connected from Twilio through a SIP trunk)](https://retell.discourse.group/t/i-m-trying-to-use-a-toll-free-number-connected-from-twilio-through-a-sip-trunk/127) [[3] Local VOIP Provider not giving E.164 Format](https://discord.com/channels/1186424376300679209/1444865486499221588) ​

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

Thanks for the follow-up, @KYB- LPP. I'll get back to you soon.

javascript
import Retell from 'retell-sdk';
const client = new Retell({
  apiKey: 'YOUR_RETELL_API_KEY',
}) ;
const phoneNumberResponse = await client.phoneNumber.import({
  phone_number: '+14157774444',
  termination_uri: 'someuri.pstn.twilio.com',
}) ;
console.log(phoneNumberResponse.inbound_agent_id) ;

[(3) ]() For detailed setup guidance, see: [Custom Telephony Overview]() [(1) ]()

​ To learn more, see the sources I considered: [[1] Custom Telephony Overview](https://docs.retellai.com/deploy/custom-telephony) [[2] Twilio](https://docs.retellai.com/deploy/twilio) [[3] Import Phone Number](https://docs.retellai.com/api-references/import-phone-number) ​

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

​ To learn more, see the sources I considered: [[1] Outbound Calls (Make Calls)](https://docs.retellai.com/deploy/outbound-call) ​

### Answer ### Answer When making outbound calls, you (the caller/business) pay the charges, not the person receiving the call. [(1) ]() For Retell-purchased US numbers calling China: Retell supports international calling to a limited set of countries. The documentation mentions support for calling to 15 countries for Retell-purchased numbers. However, I don't have specific information in my sources confirming whether China is included in that supported country list or what the exact per-minute rates would be. What I can confirm: - For imported numbers (via custom telephony/SIP trunk) , international calling depends on your telephony provider's settings and rates. - If using a provider like Twilio via SIP trunk, you would pay Twilio's international calling rates to China. Recommended next steps: 1. Check the international calling documentation for the supported country list and rates: [International Calling Documentation]() 2. If China isn't supported natively, you'd need to use custom telephony with a provider that supports China calling Would you like me to provide more details on setting up custom telephony for international calling?

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