Hi! Does anyone know how I can set it up to receive an email when a customer pays an invoice online? Thanks

Hi there, @aryn2.

To receive email notifications when your customer pays the invoice online, you'll need to turn on this feature in your merchant account. 

Here's how:

1. Sign in to https://merchantcenter.intuit.com.
2. Under Account, select Settings & Alerts.
3. Choose Yes under Receive Credit card Deposit Notification.

Once done, you'll now receive an email within 1 hour after any transactions from QuickBooks Payments such as:

• Approval emails
• User invitations
• Confirmation code
• Notifications from a transaction, deposit, or recurring charge (ReBill)
• Forms requested from the Merchant Service Center (MSC)

For additional information, you can read through this article: Take and process payments in QuickBooks Online. 

Also, to know when QuickBooks payments deposit your customer payments into your bank, you may visit this link for the detailed instructions: Deposit times for QuickBooks Payments. From here, you'll learn on how to check your product's deposit speed, status of the deposit, and specific customer payments. 

Keep in touch with me if you have other payment notifications concerns. I'll be around whenever you need further assistance. Take care always.