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] Dynamic Variables](https://docs.retellai.com/build/dynamic-variables) [[2] Create Phone Call](https://docs.retellai.com/api-references/create-phone-call) [[3] Discord message from @chiefbeef300_ on 2025-02-12](https://discord.com/channels/1186424376300679209/1186462578310910112/1339044819498041444) ​

### Answer Yes, you can achieve this using the Inbound Call Webhook. [(1) ]() For phone calls, Retell provides the system variable

{{user_number}}

which represents the user's phone number (from_number for inbound calls, to_number for outbound calls) . To save it under a custom variable name like

phone

, you can: 1. Use the Inbound Call Webhook - This webhook receives the

from_number

in its payload, and you can return it as a custom dynamic variable with your preferred name. 2. In your webhook response, return it in the

retell_llm_dynamic_variables

field:

json
{
  "phone": "+12137771234"
}

[(2) ]() A community member confirmed this approach works: creating an inbound webhook that reads the

from_number

and returns it as a dynamic variable. [(3) ]() Alternatively, you could reference

{{user_number}}

directly in your prompts and tool configurations, as it's a default system variable available for phone calls. [(1) ]()