I want to add comments to the monthly financial reports, but I want to keep the reports online (ie. I don't want to download to XLS). Can I do this in QBO or an Add-On?

Thanks for checking in with us, krystajfox.

Though there's no field to enter a comment in the financial reports. What we can do is to memorise it in QuickBooks Online (QBO). Then,  enter a descriptive name or comments for the report. Let me show you how:

1. Open the financial report. 
2. Select Customise.
3. Once the report is customised the way you like it, select Run report, then tap Save customisation.
4. In the Custom report name field, enter a descriptive name or comment for the report.
5. If you want to add this report to a group, choose Add this report to a group, then choose an existing group or create a new one. Grouping reports allows you to organise them in your list of memorised reports. You can then create scheduled emails that send all reports in the group to the recipients you specify. This feature is only available in QuickBooks Online Essentials or Plus.
6.  Select Share with if you want to share the report with other users, Then choose the users. Sharing the report will add it to other users' My custom reports.
7. Press Save.

For more details about this one, see the Memorise reports in QuickBooks Online article. You can also customise other reports in your account and memorise it. Feel free to visit our Reports page for more insights about managing your reports in QBO.

I hope that this response finds you with a smile. Keep me posted if you need a hand with exporting your data or any QBO related. I'm always here to ensure your success. Take care always.