What is an Overdraft?

An overdraft occurs when there isn't enough money in an account to cover a transaction or withdrawal, but the bank allows the transaction anyway. Essentially, it's an extension of credit from the financial institution that is granted when an account reaches zero. The overdraft allows the account holder to continue withdrawing money even when the account has no funds in it or has insufficient funds to cover the amount of the withdrawal.

Basically, an overdraft means that the bank allows customers to borrow a set amount of money. There is interest on the loan, and there is typically a fee per overdraft. With an overdraft account, a bank is covering payments a customer has made that would otherwise be rejected, or in the case of actual physical checks, would bounce and be returned without payment.

Your bank can opt to use its own funds to cover your overdraft. Another option is to link the overdraft to a credit card. If the bank uses its own funds to cover your overdraft, it typically won't affect your credit score. When a credit card is used for overdraft protection, it's possible that you can increase your debt to the point where it could affect your credit score. However, this won't show up as a problem with overdrafts on your checking accounts.

If you don't pay your overdrafts back in a predetermined amount of time, your bank can turn over your account to a collection agency. This collection action can affect your credit score and get reported to the three main credit agencies: Equifax, Experian, and TransUnion. It depends on how the account is reported to the agencies as to whether it shows up as a problem with an overdraft on a checking account.

Some but not all banks will pay overdrafts automatically, as a courtesy to the customer (while charging fees, of course.) Overdraft protection provides the customer with a further tool to prevent embarrassing shortfalls that reflect poorly on your ability to pay.

Usually, it works by linking your checking account to a savings account, other checking account, or a line of credit. If there's a shortfall, this source gets tapped for the funds, ensuring that you won't have a check returned or a transaction/transfer declined. It also avoids triggering a non-sufficient funds (NSF) charge. 

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