Hi there, jason30.
We're currently unable to send an attachment to multiple customers in QuickBooks Online. However, you can download the attachments and manually email them to your customers.
Here's how:
- Click the Gear icon located in the upper right-hand corner.
- Under Lists, click Attachments.
- Find the attachment, and click the Download link under the Action column.
You can also check this article for more information: Attachments in QuickBooks Online.
If there's anything else you need help with QuickBooks, please let us know. Thanks.