It’s typically smart to pay off debt all at once if possible because you’ll reduce how much you pay in interest over time. It can also help your credit score if you pay down large credit card balances that are affecting your credit utilization ratio. But you might miss out on opportunities to invest your money, and your credit score could take a small hit if you immediately pay off a loan. When a loan is paid off, it closes a credit account on your credit report. A closed credit account no longer adds to the average age of your credit accounts, which is a factor in determining your credit score.