Can I add extra column for invoice in QuickBooks Online ??

I'm glad you made it here, rikas-primroseqa.

In QuickBooks Online (QBO) you are allowed to add up to three custom fields on the invoice. Each data field can be customized based on your preference and can be displayed in your invoice.

You'll want to make sure to check the box for the Custom field added so it reflects on the invoice. Below is a screenshot for your better view:

Learn more about adding custom fields through this article: How to add custom fields to invoices.

The next step is to use the template when creating the invoice. I'll show you how to do it:

1. Open an invoice.
2. Click Customize.
3. Choose a template.
4. Fill in the necessary information and click Save and close.

You can also check out this article to learn more about customizing templates in QBO: Customize invoices, estimates, and sales receipts in QBO.

If you want to review the invoices you made, run the Invoice List. Pull this up by going to the Reports menu at the left pane then type Invoice List on the search bar.

Visit us again if you need help or other questions. It will be my pleasure to help. Stay safe and have a nice day.