Greetings, @SCP.
Thank you for taking the time posting in the QuickBooks Community. I'd be happy to help share some details about merging two companies in QuickBooks Online.
You can merge a QuickBooks Desktop file into the online version by importing the file into a new QuickBooks Online company as long as it is within the first 60 days of being created. If the company is more than 60 days, you will need to set up a new one.
However, merging two company data files into one company is currently not available in QuickBooks Online. In the meantime, you can manually export a list from one QuickBooks Online company and import it into the company you want to keep.
Here's how:
For additional help, you can also reach out to our phone support. They have everything needed to help you further.
This will get you on the right track! Drop me a comment below if you have any other questions about merging two QuickBooks Online companies into one company. I'll be happy to help you out.