Add Credit Card Fee to Invoice
How do I add a credit card fee of 3% to an invoice based on the total amount?
I assume you mean an invoice to a customer, and not an invoice from a vendor.
In this case, you will need to setup an Item in your Item list. Follow this path:
Lists > Item List
Press Control-N. This allows you to create a new Item.
Once in the New Item screen, make this item an "Other Charge."
For the Item Name, call it Convenience Fee (or some other name that is meaningful to you). Don't make it a sub-item.
Enter a description if you want one to appear on your customers' invoices. Otherwise leave the Description blank.
For the Amount, enter 3%.
For the Account, you have a choice. You can either create a new Income account for these fees, or you can choose your Merchant Fee Expense account (assuming you have one). I suggest you talk to your CPA about this - he/she might have a preference, and it would be best to find out what it is now, rather than waiting until tax time.
Click OK when you are finished. You may now use this item on your customers' invoices.
Keep in mind that QB will only calculate 3% of the items above this item on the invoice screen. QB will not calculate 3% below this item. This means that QB will not include sales tax in the 3% calculation.
I hope this helps. Thanks for writing.