Hello there, @catherinek.

We're unable to change the sub-customers' information in batch. You’ll have to manually enter the information or export and import the list in QuickBooks.

Here’s how to export to excel:

1. Go to the Sales menu and choose Customers.
2. Select the Customers name and click the Export icon next to the Print icon.
3. Choose Export to Excel.

Once done, you can check out these articles for further guidance on importing the information on the excel file to QuickBooks Online:

• Import customer or vendor contacts from Outlook, Excel, or Gmail.
• Which contact fields are imported from Excel?

Stay in touch if you have follow-up questions. I’m here anytime you need help. Keep safe always.