Hello there, @bl11.

You can go to the Audit log and check who paid the bill in QuickBooks Online (QBO).

Here's how:

1. Go to the Gear icon.
2. Under Tools, select the Audit log.

Once done, you can hit Filter the button and enter the information needed to narrow the results and click Apply.

For more detailed information, you can refer to this article: The Audit Log: What it is, How to Use it.

Also, let me share this article in case you want to learn more about how to customize your reports in QuickBooks Online.

Keep posting in the Community space if you have any other questions. Have a nice day!