Update ticket edit or create fields based on other custom fields value in the JSM form

[yaron]

Hello,
We have a request for JSM project with portal access.
We are looking for a way to update single select custom field which is not in the related JSM request form based on the value selected for another field which is included in the related request form via the portal.

Are there any rules, smart values which enable access to a select field option existing in the request form but not in the related issue type CREATE and EDIT screens.

Thanks, 

Yaron

[Olha Yevdokymova_SaaSJet]

Hi @yaron 

What Jira Service Management Can (and Can’t) Do Natively

In JSM, a field can only be updated if it is:

1. On the portal request form, and

2. On the Work Item Type’s Create/Edit screen

If a field is not on the screen scheme, then:

• It will not accept values from the portal

• Automation rules cannot update it

• Smart values cannot read/write it

• It behaves as if it doesn’t exist

So with native JSM, you cannot do:

“When the customer chooses X → update another custom field that isn’t shown on the form.”

That’s why your update is failing — Jira simply blocks writes to hidden issue fields unless they’re on the screen.

 A Practical Workaround With Smart Forms for Jira

If you want to update an internal custom field without showing it to the requester, Smart Forms for Jira (developed by my team) solves this cleanly.

Smart Forms lets you:

✔ Add hidden fields

Hidden fields don’t appear on the request form, but they still submit structured data.

✔ Use conditional logic

You can set hidden fields automatically based on what the user selects.

✔ Map hidden fields directly to any Jira custom field

No need to add that Jira field to the JSM create screen.

 Example matching your case

Goal:
Update a single-select Jira custom field even though it’s not on the portal form.

How to configure this:

1️⃣ In Smart Forms, add the visible field

Example:
Field A (Dropdown shown on the form)

2️⃣ Add a Hidden field

Example:
Internal Category (Hidden) – requester will never see it. Add default response value - the actual value form hidden field

3️⃣ Add conditional logic

For example:

• If Field A = “Hardware” → Set hidden field + default response value= “Category A”

• If Field A = “Software” → Set hidden field + default response value = “Category B”

• If Field A = “Network” → Set hidden field + default response value= “Category C”

4️⃣ Create new work item and Map the Hidden field → your Jira single-select custom field

This mapping works even if the Jira field does not appear on the Create/Edit screens.

5️⃣ When the requester submits the form

• The customer only sees Field A

• Smart Forms fills the hidden field for you

• Jira receives the correct value in the custom field

• No portal clutter, no screen scheme changes, no manual work

Why this solves your problem

Jira won’t let you update internal fields unless they’re on the screen.
Smart Forms bypasses this limitation by mapping its form fields—including hidden ones—directly into Jira fields.

So you end up with:

✔ Clean portal forms
✔ Internal fields populated automatically
✔ No need to expose internal logic or extra fields to customers
✔ No need to modify your JSM screen scheme

[Laura Campbell]

Hi @yaron ,

Do you mean can a hidden field have the value set based on a visible field? So if a customer selects priority 'high', some other field value gets set?

[Marc -Devoteam-]

Hi @yaron 

I'm a bit confused on your question.

Can you add screenshots to clarify, (I think you are not using the terminology correct, and this is throwing mwe off-topic)