Thanks for visiting us here in QuickBooks Community, harpist.jlh.

I'm here to help and provide you with some option on how to print customer's information for mailing invoices or statement. 

As of now, QuickBooks Online (QBO) doesn't have an option to print customer's name and address on an envelope. As a workaround for mailing invoices, you might want to consider printing a packing slip as an alternative. You can attach it inside your shipping pouch or in the package itself. 

Here's how: 

1. On the left navigation bar, click Sales.
2. Click on the Customers tab.
3. Check the boxes next to each invoice or sales receipt for which you want to print a Packing Slip/Delivery Note.
4. Click the Batch Actions drop-down.
5. Choose Print packing slip.
6. The print preview screen will open so you can select printing options, preview and print.

For additional reference and to learn more about packing slip, you can check this article: How to create a packing slip or packing slip.

I can see how this feature would be helpful for you, I recommend sending feedback directly to our product developers so they'll be able to include this in their next product update.

Here's how to send feedback: 

1. Click the Gear Icon.
2. Select Feedback.
3. Click Next, and choose Feedback under Category option.
4. Select Save.

You're always welcome to drop by if you have any other questions about QBO. Wishing you and your business continued success.