How much does QB charge to the customer when the customer pays with a Credit Card?

No charge for your customers, only to you.

Check pricing https://quickbooks.intuit.com/legal/payments/standard-pricing-schedule/

How much does it charge per transaction?

Thanks for getting back to us, natalia1.

Allow me to help you and share some additional information about charges via credit card in QuickBooks Online.

If you are using merchant services when processing payments for invoices, the charges vary depending on:

• whether or not you swiped the card (sometimes called card-present transactions) or entered the number manually (which costs more since the card's assumed to not be present, therefore the transaction carries more risk).
• what the card type is (reward cards cost you more).
• what industry you're in.

You can get more details in these articles:

• Credit card processing fees.
• A quick guide to Credit Card processing.
• Accept credit cards, debit cards, and bank transfers with QuickBooks payments.
• Everything You Ever Wanted to Know About Credit Card Fees.

If you require more information about the credit card charges, you can reach out to our Merchant Services Center so they can discuss the accurate charges for you.

Just go to https://community.intuit.com/browse/payments-contact-us.

You can always get back to me if you have any other concerns about credit card charges in QuickBooks Online. I'll be around to answer them for you.

Is it possible to set up Credit Card payments so the customer IS charged the processing fees? I would like the payment transaction to automatically add the fees to the customer’s payment. Then, when received in QBE, the paid fees would go to one account (eventually offset by the fees charged by Intuit) and the proceeds would pay the customer’s invoice. 

We’re a small association with annual dues around $1500/year and expect only about 20% of our 150 members would use credit card payment and 25% ACH. We don’t want all members to be subsidizing the fees for the few paying by CC/ACH. 

Since we don’t know in advance who will pay with a CC, we can’t add the fees to the invoice. It’d be great if it was automatic when paying the invoice with CC/ACH. 

@DEHolz 

We may have a workaround to lower your cost. By default, you may utilize MP to only accept ACH payment for free. For anyone who want to pay by credit card, ask them to utilize MP once they want to proceed. They will pay your invoice by credit card and the fee will be charged to them.

https:// melio.grsm.io/quickbooks