In WHMCS, custom fields allow you to collect and store additional information about clients, products, services, and more. These fields provide flexibility in tailoring WHMCS to your specific business needs. Here's how you can work with custom fields:

Client Custom Fields:

1. Creating Custom Fields:

   • Navigate to "Setup" > "Custom Client Fields."
   • Click on the "Create New Field" button.
   • Configure the field options, such as field type, name, description, and validation rules.

2. Editing Custom Fields:

   • In the "Custom Client Fields" section, click on the name of the field you want to edit.
   • Modify the field settings as needed and save changes.

3. Using Custom Fields:

   • Custom fields will be visible on the client's profile page in the admin area and can also be displayed on the client registration form.

Product/Service Custom Fields:

1. Creating Custom Fields:

   • Navigate to "Setup" > "Custom Fields."
   • Select the "Product/Service" tab.
   • Click on the "Create New Field" button.
   • Configure the field options, such as field type, name, description, and validation rules.

2. Assigning Custom Fields to Products/Services:

   • In the "Product/Service Custom Fields" section, click on the "Assign to Products" button next to the field you created.
   • Select the products or services to which you want to assign the custom field.

3. Editing Custom Fields:

   • In the "Product/Service Custom Fields" section, click on the name of the field you want to edit.
   • Modify the field settings as needed and save changes.

Invoice Custom Fields:

1. Creating Custom Fields:

   • Navigate to "Setup" > "Custom Fields."
   • Select the "Invoice" tab.
   • Click on the "Create New Field" button.
   • Configure the field options, such as field type, name, description, and validation rules.

2. Assigning Custom Fields to Invoices:

   • In the "Invoice Custom Fields" section, click on the "Assign to Invoices" button next to the field you created.
   • Select the invoices to which you want to assign the custom field.

3. Editing Custom Fields:

   • In the "Invoice Custom Fields" section, click on the name of the field you want to edit.
   • Modify the field settings as needed and save changes.

Ticket Custom Fields:

1. Creating Custom Fields:

   • Navigate to "Setup" > "Custom Fields."
   • Select the "Ticket" tab.
   • Click on the "Create New Field" button.
   • Configure the field options, such as field type, name, description, and validation rules.

2. Assigning Custom Fields to Tickets:

   • In the "Ticket Custom Fields" section, click on the "Assign to Tickets" button next to the field you created.
   • Select the tickets to which you want to assign the custom field.

3. Editing Custom Fields:

   • In the "Ticket Custom Fields" section, click on the name of the field you want to edit.
   • Modify the field settings as needed and save changes.

Custom fields in WHMCS provide a powerful way to collect and organize specific information relevant to your business. They can be used to enhance client profiles, gather additional product/service details, capture invoice-specific data, and streamline ticket management.