using customer email addresses

Hi there, gmapowers.

Yes, you can use customer email addresses in QuickBooks Online for simple correspondence without invoicing. QuickBooks Online allows you to send emails directly to your customers from the platform. 

You can use this feature to send general correspondence to your customers, such as statements, reminders, payment request, announcements, or other non-invoice-related messages. Here's one of the articles you can use as a reference in utilizing the email feature: Email or print multiple sales forms in QuickBooks Online.

I've also added this link to learn how you can Add and manage customers in QuickBooks Online.

Let me know if you still need my assistance or have other customer-related concerns. I'll be here to help.