Hello there, jbailey1122,

In QuickBooks Online, you'll have to add the attachments to the invoice one by one. You can look online for a third-party application that can do this and will allow you to integrate with QuickBooks Online.

You can also upload attachments directly in QuickBooks Online:

1. Click the Gear icon.
2. Under LISTS, select Attachments.
3. Click the Drag/Drop files here or click the icon to browse for available attachments on your drive.

Check this article to see what type of transactions you can add attachments: Attachments in QuickBooks Online.

This can also come in handy: Customize invoices, estimates, and sales receipts in QuickBooks Online.

Let me know if you have other questions.