5 different companies, all invoices/estimates sent with the same email. How can I use a different email address for each company to send invoices or estimates?

Good day, cbcservice1514.

You can update the email address from each of the company files Account and Settings one at a time. I'll walk you through the steps below:

1. Go to the Gear icon.
2. Choose Account and Settings.
   
3. Click the Company tab.
4. From the Contact info section, update the email address from the Company email field.
5. Click Save, then Done.
   

I've got some article that might help you with sending invoices and estimates in QuickBooks Online (QBO):

• Send an invoice.
• How to Send Estimates, Quotes, & Proposals.

The Community is always open for any queries you may have. Wish you all the best of luck.