QuickBooks Online (QBO) doesn't have a direct option to automatically pass credit card transaction fees to customers, @rey6.

As a workaround, you can manually add a surcharge or fee line item on the invoice to cover the credit card processing fee. Inform your customers about the fee in your payment terms or add it in the invoice notes. Then, create a fee product/service line item.

Here's how:

1. Go to the Gear icon, then choose Products and Services.
2. Click on New, then pick Service.
3. Enter the name of your service item. (For example, Processing Fee).
4. Select the account you'd use to track the processing fees.
5. Then, click Save and Close.

Once done, add the processing fee as an additional line item to your invoice to charge your customers:

1. Go to Sales & Get Paid and select Invoices.
2. Locate the invoice you wish to update, then click on View/Edit.
3. Add a new line item and select the service item you've created.
4. Review and send after.
   
   

You can check out this article for the detailed steps: Manually add service fees to invoices in QuickBooks Online.

For your second question, please visit our application website and search for a third-party app that can be integrated with QuickBooks to process your credit card transaction fees, ensuring they are accurately accounted for in the system.

If you have any additional questions or require further assistance, please respond to this message.