Does anyone know if you can add a custom field to invoices and estimates, basically a subject line with a brief description of what the quote is for, that you can also see when viewing all estimates and invoices in a list?
Yes, there's an option to add the custom field, Sara Taylor.
We can create an invoice or estimate template and add the field in the Custom Form Styles settings. Please take note that the modification will apply to all templates.
Here are the steps:
I've got this article for reference: How to add custom fields to invoices.
You can also import a template in DOCX format from Word. Before doing so, make sure to turn on the import option in QuickBooks Labs.
Then, follow the steps in this article: Import custom form styles for invoices or estimates.
Finally, to view all the lists, we can run the Transaction List by Customer and customize the columns to add the custom fields.
We're always here if you need more help with QuickBooks Online. Thanks.