Credit balance
A credit balance is an amount that the card issuer owes you.
Each time you make a payment, credits are added to your account. It may also be added when you return something you bought with a credit card or because of rewards you have earned or a mistake in a prior bill. When the total of the credits exceeds the amount you owe, your statement shows a credit balance.
Credit card interest rate
A credit card’s interest rate is the price paid for borrowing money.