It's great to see you here in the Community, John!
We recognize that sending your invoices through fax can help streamline your workflow. However, this feature is currently unavailable in QuickBooks Online (QBO).
In the meantime, you can use a third-party app to send faxes. You can find an app directly from QBO by following these steps:
From the left navigation panel, choose Apps.
Open the Find apps tab.
Type the app name in the search bar or select the Browse category dropdown menu to explore different apps.
To help improve your experience with QBO, your valuable feedback goes directly to our product development team for review and consideration.