Thanks for coming back, AvonDM. 

There is no file size limit in QuickBooks Online (QBO) version so you don’t have to worry about entering too many customers, accounts or items, and there are no transaction limits. However, when converting a QuickBooks Desktop file (Enterprise, Premier, or Pro versions) to QBO, file size (MB) doesn't matter, however, targets do. To convert your Desktop data to Online version, the Desktop file must be less than the following limits:

• QuickBooks Desktop Enterprise 2021 (with latest releases) and newer 750,000 targets.
• QuickBooks Desktop Pro and Premier 2018 (with latest releases) and newer 750,000 targets.
• QuickBooks Desktop Enterprise 2020 and older 350,000 targets.
• QuickBooks Desktop for Mac 350,000 targets.
• QuickBooks Desktop Pro and Premier 2018 and older 350,000 targets.

For a company that has added 2.2 million targets, we'll need to look for a third-party application that can help you with this one. You can go to the QuickBooks Desktop apps website and find a third-party application that can help you with the software data conversion. Any questions about integrating the app into your Online account are best handled by the third-party app provider.

Let me share some resources that you can browse and use as a reference in managing and navigating around in QuickBooks Online: 

• Video Tutorials for QuickBooks Online - You can watch videos that can help you perform the most vital features of the program.
• Small Business Webinars and Trainings - Join our live QuickBooks webinars for more in-depth knowledge on how you can maximize the use of QuickBooks to manage your finances.

The Community always has your back, and I'm just a post away should you ever need anything. Just leave a comment below and I'll get back to you. Have a great day ahead.