I'll share some information about importing IIF files into QuickBooks Online, sighting.
Currently, the supported file formats you can use to import data to QuickBooks Online are CSV, XLS/XLSX, and Google Sheets.
For IIF files, you may convert them to a supported format before you can import them. There are plenty of file converters that you can search online. Once you're all set up and ready, refer to the articles below to be guided in importing your data:
More information can be found in the following article: Common questions about importing data to QuickBooks Online.
Additionally, I've attached this helpful resource that you can access to get visual guides in performing your QBO tasks: Learn about QuickBooks Online with how-to videos.
If you have any other concerns about managing your data in QuickBooks, please don't hesitate to get back here. I'm just around the corner to lend a hand.
