How do I add a second email address to my customer so the invoice gets sent to both email address'?

Welcome to the QuickBooks Community, Jason. I'll be glad to help you add a second email address to your customer's profile in QuickBooks Online (QBO) to send your invoices to both email addresses.

In QBO, you can add multiple email addresses for a customer by separating them with a comma. Here's how:

1. Go to Customers & Leads and select Customers.
2. Click the customer's name, then Edit.
3. In the Email section, enter the email addresses separated by a comma (sample1@intuit.com, sample2@intuit.com).
4. Click Save.

Moreover, you can customize sales forms in QBO to personalize their appearance and content.

Feel free to visit us in the Community if you need further assistance adding a second email address for your customer in QBO, and we'll respond promptly to help. Stay safe, and have a wonderful day ahead.