Subflow referenced-flow rules
Key Takeaway
Activate the flow that a Subflow element calls before real users run it. Without an active version, that flow runs only for users who have the "Manage Flows" permission.
The Subflow element lets one flow call another flow in the org. The flow that makes the call is the parent flow, and the flow it calls is the referenced flow, also known as the child flow. The main payoff is reuse: you build a common task once and reuse it in many flows, so a change happens in one place. Rules decide which flows you can call, which version runs, and how data moves between the two flows.
Reusing a common task
Salesforce recommends building small utility flows for common tasks, such as authorizing a credit card amount, and calling them from many flows.
For example, imagine four flows that post the same Chatter message. You can move that post into one referenced flow and call it from all four. A later change then happens in one flow instead of four, which leaves fewer chances to miss or misconfigure something.