Q: How do waiters or restaurants complete your transaction after they run your credit card for the meal but before you add the tip?? Do they run your card twice or is the transaction on hold until you fill in the tip amount?
A: I work at a restuarant and your "on hold" idea is pretty much right on. In our case, we swipe the card and enter the amount of the check. Then we take that check to the customer to sign and add the tip (if they wish). After that we go back to the credit card machine and "recall" that ticket by using a transation number on the top of the ticket. We are prompted by the machine to enter the tip amount and "finish" the transation.