Key Takeaways
- APR measures what borrowing costs you per year, including fees on many loan types.
- APY measures what a deposit account earns per year, accounting for compounding.
- Compounding frequency makes APY higher than the stated interest rate on savings accounts.
- On loans, a lower APR means less total cost; on savings, a higher APY means more earned.
- Federal law requires lenders and deposit institutions to disclose APR and APY respectively.
- Consulting a licensed financial adviser helps you apply these figures to your own situation.
Option A
Annual Percentage Rate (APR)
The true cost of borrowing, expressed as a yearly percentage.
Best for: Comparing the cost of loans, credit cards, and mortgages before you borrow.
Option B
Annual Percentage Yield (APY)
The real return on savings after compounding is factored in.
Best for: Evaluating how much a savings account, CD, or money market account will actually earn.
When you are comparing loans or credit cards
Annual Percentage Rate (APR)
APR lets you compare the yearly cost of debt across different lenders on a consistent basis. A lower APR generally means less paid over the life of a loan.
When you are comparing savings accounts or CDs
Annual Percentage Yield (APY)
APY reflects the effect of compounding, so it shows the actual return your deposit will earn in a year, not just the base interest rate.
When you are deciding whether to save or pay down debt
Compare both figures directly
If your debt's APR exceeds the APY your savings can earn, paying down that debt typically produces a better financial outcome than saving at a lower rate.
What APR actually measures
Annual Percentage Rate is the yearly cost of borrowing money, expressed as a percentage of the loan balance. Federal law, specifically the Truth in Lending Act, requires lenders to disclose APR so consumers can compare loan offers on equal footing.
APR goes beyond the stated interest rate. For most loan types, it folds in origination fees, discount points, and certain other charges, spreading them across the loan term. That is why a mortgage advertised at one interest rate often carries a slightly higher APR: the fees are included in the calculation.
Credit cards work somewhat differently. Credit card APR is typically just the periodic interest rate multiplied by the number of periods in a year, without compounding baked in. Carrying a balance means that interest accrues daily on most cards, which can push the effective cost above the stated APR. See how compound interest works against debt for a closer look at that mechanic.
When comparing loans, the APR is the number to prioritize over the nominal interest rate alone, because it captures more of the true cost.
What APY actually measures
Annual Percentage Yield is the real rate of return on a deposit account over one year, with compounding included. The Truth in Savings Act requires banks and credit unions to disclose APY on deposit products, giving savers a standardized number for comparison.
The difference between APY and a simple interest rate comes down to how often interest is calculated and added to the balance. If a savings account pays interest monthly, each month's interest earns interest in subsequent months. That feedback loop is compounding, and APY captures its full effect over a year.
Compounding frequency and APY
Interest can compound daily, monthly, quarterly, or annually. The more frequently it compounds, the higher the APY relative to the nominal rate. When comparing deposit accounts, always use APY rather than the stated interest rate so that compounding differences are already accounted for in the number you see.
A higher compounding frequency produces a higher APY from the same base rate. An account compounding daily will have a marginally higher APY than one compounding monthly at the same nominal rate. For most everyday savings accounts the difference is small, but it grows with larger balances and longer time horizons. How savings accounts, money market accounts, and CDs differ covers how compounding schedules vary across account types.
Side-by-side comparison
Putting both figures in the same frame shows where each one belongs in a financial decision.
| Criterion | APR | APY |
|---|---|---|
| What it measures | Cost of borrowing per year | Return on deposits per year |
| Includes compounding | No (simple rate plus fees) | Yes (compounding included) |
| Regulated by | Truth in Lending Act | Truth in Savings Act |
| Used on | Loans, credit cards, mortgages | Savings accounts, CDs, money market accounts |
| Lower is better or higher is better | Lower means less borrowing cost | Higher means more earned |
| Fees included | Yes, on most loan types | Not applicable |
The most practical application is direct comparison: if you carry a credit card balance with a 22% APR and your savings account offers a 4.5% APY, the debt costs you far more than your savings earns. In that scenario, paying down the balance produces a better return than keeping excess cash in the savings account, all else being equal.
For a broader vocabulary of personal finance terms, financial terms every US adult should recognize provides a useful reference.
This article is for general informational purposes only and is not personalized financial or investment advice. Consult a licensed financial adviser, accountant, or attorney for guidance specific to your situation.