### Answer The error you're seeing is because Retell-purchased numbers have limited international calling support. Currently, numbers purchased from Retell can only make calls to US numbers. [(1) ]() For international calling to Turkey (+90) , you have two options: *1. Use Custom Telephony (Imported Numbers) * International calling depends on your telephony provider's settings when using imported numbers. [(2) ]() You can import a number from providers like Twilio or Telnyx and configure international dialing permissions through their platform. For Twilio specifically, search "geo" to find the "Voice Geographic Permissions" setting to enable dialing to Turkey. [(3) ]() 2. Configure Outbound Allowed Countries When creating or updating a phone number via the API, you can specify

outbound_allowed_countries

with the ISO 3166-1 alpha-2 country codes you need:

json
["US", "CA", "TR"]

[(4) ]() However, this setting works in conjunction with your telephony provider's permissions—if using Retell-purchased numbers, the underlying provider restrictions still apply. **Recommended path**: Import a number from Twilio or Telnyx with Turkish calling enabled, then use that number for your outbound calls to Turkey.

​ To learn more, see the sources I considered: [[1] Debug outbound connection issues](https://docs.retellai.com/reliability/debug-outbound-call) [[2] Outbound Calls (Make Calls)](https://docs.retellai.com/deploy/outbound-call) [[3] 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) [[4] Create Phone Number](https://docs.retellai.com/api-references/create-phone-number) ​

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