How do I apply a custom field to just one sub task in an entire project?

[Lisa Hinz]

One of our Sub Tasks in workflow is AFC Approved. There is an approval number provided and I would like to apply AFC Approval only on the sub task referenced above. When I created the custom field, it applies on all Sub Tasks on the project.

[Petter Gonçalves]

Hello Lisa, 

Welcome to Atlassian community!

Sub-task is an entire level of issue-types on JIRA. Explaining better, we have two levels of Issue types:

Standard = Related Bugs, Tasks, Stories, etc (Created by default)

Sub-task = Related to Sub-tasks (Created by default)

That been said, you can create a new issue type under the Sub-task level to define specific fields to it and set your current sub-task with this new issue type. Here are the steps:

- Navigate to JIRA Settings > Issues > Issue Types > Add Issue Type

- Add a name and select the box "Sub-task Issue Type":

- Add the issue type to the issue type scheme of your project and move your issue to the Issue Type you created

Doing the steps above, you will be able to set screens and fields only to this specific issue type.

For more details on how you can set screens to the new issue type, you can check the documentation below:

- Defining a Screen

Let us know if this information helps.

[Management]

It does not solved the question, user states that when she created the custom field, it applies on all Sub Tasks on the project.

The solution does not mention how to add a specific field for one subtask only