### Answer Based on the available documentation, the built-in SMS functionality in Retell AI is designed to send SMS from the agent's number to the user's (caller's) number — not to a third-party transfer destination. [(1) ]() [(2) ]() The SMS Node and Send SMS tool specifically send "an one way SMS from the current agent number to the user's number." Workaround options: If you need to send an SMS to the person you're transferring to (not the original caller) , you would likely need to: 1. Use a custom function/webhook — Set up a custom function that calls an external service (like Twilio directly via n8n or your own backend) to send SMS to any arbitrary number you specify. [(3) ]() 2. Build external logic — Before the transfer, trigger a webhook that sends the SMS to your transfer destination number using an external SMS API. This isn't natively supported out-of-the-box with the standard SMS Node, which only targets the caller's number. Would you like guidance on setting up a custom function approach?

​ To learn more, see the sources I considered: [[1] SMS Node](https://docs.retellai.com/build/conversation-flow/sms-node) [[2] Send SMS](https://docs.retellai.com/build/single-multi-prompt/send-sms) [[3] Discord message from @conect242004 on 2025-06-11](https://discord.com/channels/1186424376300679209/1294891368505937952/1382375333344317490) ​

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