# Transfer to External (/docs/workflows/reference/category/session/transferToExternal)

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Transfer the call to an external number. Supports BYO.

Transfers the current call to an external phone number or dial string, handing the caller off outside the workflow. The transfer target accepts a `$(name)` variable, so it can be chosen dynamically earlier in the flow, and supports bring-your-own (BYO) carrier destinations. Outbound SIP Trunk selects which of your configured SIP trunks the transfer leaves on; leaving it as Default uses standard outbound routing. Only trunks with an outbound address configured can carry a transfer, so a trunk missing one is not offered. To route to an agent or queue inside Sharpen instead, use the corresponding Sharpen transfer node.

**Category:** Session  
**Provider:** Core  
**Latest version:** 1.0.0

## Fields

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| Transfer Number (`transferNumber`) | string | Yes | Phone number or dial string that will be transferred to. Supports BYO. |
| Outbound SIP Trunk (`sipTrunk`) | dynamicDropdown | No | Which of your configured SIP trunks to place the transfer over. Leave as Default to use standard outbound routing. |

## Exits

- `invalidInput` (system)
- `fallback` (system)

System exits (auto-injected, hidden when unwired): `invalidInput`, `fallback`.