What APY Actually Means

The plain answer

Annual percentage yield, or APY, is the yearly return a deposit account would earn if its rate stayed the same and the interest remained in the account. APY includes compounding, so it is the useful figure for comparing savings accounts, money market accounts, and certificates of deposit. A higher APY pays more, but fees, balance rules, and future rate changes can erase the advantage.

How it actually works

Interest is money a bank or credit union pays you for keeping money on deposit. The interest rate is the rate used to calculate each payment. That rate alone does not show the effect of earning interest on earlier interest.

Compounding happens when earned interest is added to your account balance. Later interest can then be calculated on your deposits and the interest already credited. APY turns the stated rate and that compounding effect into one yearly measure.

The compounding frequency tells you how often credited interest begins earning more interest. Two accounts can have the same interest rate and different APYs when their compounding schedules differ. Comparing APY with APY puts those accounts on a more consistent basis.

APY is an annualized figure, which means it expresses the result as if the money stayed in the account for a full year. You can still earn interest when you hold the account for less time, but your actual amount will depend on the balance, the time on deposit, and any rate changes.

Savings account rates are usually variable, meaning the institution can change them. The advertised APY describes the account under its current rate and stated conditions. It is not a promise that the same APY will last for a year.

What this means for you

A high APY can come with a temporary promotion, a narrow balance range, required activity, or a monthly fee. Check those tradeoffs first. Then prefer a competitive ongoing APY with no fee you expect to pay and access that matches the job of the money.

When comparing accounts, review:

• The APY that applies to your expected balance
• Whether the APY is variable or fixed for a stated term
• When a promotional APY ends
• The ongoing APY after a promotion
• Fees and the rules for avoiding them
• Deposit insurance and withdrawal access

When two accounts have similar yields, reliable access and fewer conditions often matter more than a small rate difference.

Common mistakes

A common mistake is comparing one account’s APY with another account’s interest rate. Those figures measure different things. Compare APY with APY.

Another mistake is treating a variable APY as fixed. Recheck the rate periodically and read notices from the institution. If a promotion is involved, note what happens after it ends.

Do not ignore fees or balance requirements. The advertised APY may apply only when you follow specific rules, and a fee can outweigh the interest you earn.

Related pages

• Checking vs. savings accounts
• Why your savings rate matters
• How to get a better APY
• Your emergency fund