Require a Text Field to be populated when the ‘Other’ option is selected in a picklist

Creating a Validation Rule to Selectively enforce the Field Requirement.



This image shows the completed validation rule that was created based on the below instructions in the help article. 

Step 1: In the Setup, navigate to an object that you need to have the picklist on

• In this example, we are going to use Account

Step 2: On Account we have the standard Type picklist field 

• This picklist has a value option called Other

Step 3: Create a Text field called Other Type and set the Characters to 255

Step 4: Save the field

Step 5: Now on Account create a new Validation Rule

Step 6: Give the Validation Rule a meaningful Rule Name and Description

Step 7: Use the formula below: 

AND(
ISPICKVAL(Type, 'Other'),
ISBLANK(Other_Type__c)
)

Step 8: Add an Error Message and then click Save

Pro Tip: If you are using dynamic forms, you can hide the Other Type field on the page to only be visible with the Type field is selected as Other, this will create the best user experience.