> ## Documentation Index
> Fetch the complete documentation index at: https://learn.workflow.dog/llms.txt
> Use this file to discover all available pages before exploring further.

# Return Data

> Return a value to the workflow that called this sub-workflow.

**Return Data** is available for workflows using the **Sub-Workflow** trigger.
It sends a response back to **Run Workflow**, **Loop Workflow**, or another
calling action.

## Input

| Input    | Type | Required | Description                       |
| -------- | ---- | -------- | --------------------------------- |
| **Data** | Any  | Yes      | The value returned to the caller. |

The calling action receives this value as its result or corresponding loop
item.

<Note>
  If a callable workflow finishes without returning data, callers use `null` as
  its result.
</Note>