APR vs APY is a comparison between two annual percentages that answer different questions. An annual percentage rate usually describes the cost of borrowing. An annual percentage yield describes interest earned on a deposit, including the effect of compounding under stated assumptions. You need to know which figure you are reading before comparing offers.
A loan advertising 6% APR and a savings account advertising 5% APY are not competing versions of the same product. Their fees, payment schedules, risks, and rate conditions differ. Start by separating borrowing from saving, then compare products with similar terms.
APR vs APY: what each figure tells you
APR stands for annual percentage rate. Its precise calculation depends on the product and applicable disclosure rules. For a U.S. mortgage, the Consumer Financial Protection Bureau explains that APR includes the interest rate plus points, mortgage broker fees, and certain other charges. That makes it broader than the mortgage interest rate alone.
APY stands for annual percentage yield. For U.S. deposit disclosures, FDIC guidance describes it as a rate that reflects interest and compounding frequency over a year. It helps compare deposits that credit interest differently. It does not turn every account into an identical proposition.
- For borrowing, inspect APR alongside the payment schedule, fees, and total amount payable.
- For saving, inspect APY alongside account charges, access restrictions, and the balance needed to qualify.
- For either product, check whether the advertised rate is fixed, variable, promotional, or conditional.
These examples use U.S. disclosure terminology. Other jurisdictions can define and display annual rates differently. Read the local product disclosure rather than assuming the same acronym includes the same costs everywhere.
How compounding changes a savings yield
Compounding means that interest left in an account can itself earn interest. A nominal annual interest rate and an effective annual yield can therefore differ. The familiar formula for equal compounding periods is: effective annual yield = (1 + r/n)n − 1. Here, r is the nominal annual rate as a decimal, and n is the number of compounding periods per year.
Consider a purely hypothetical deposit of $1,000 with a fixed nominal annual interest rate of 5%, compounded monthly for twelve equal periods. Assume no fees, taxes, extra deposits, or withdrawals, and leave all interest in the account. The monthly rate is 0.05 ÷ 12.
- After the first month: $1,000 × (1 + 0.05/12) = about $1,004.17.
- After twelve months: $1,000 × (1 + 0.05/12)12 = about $1,051.16.
- The effective annual yield is about 5.116%, or 5.12% when rounded to two decimal places.
Without compounding, 5% of $1,000 would be $50. In this example, leaving interest to earn more interest adds about $1.16 over the year. The calculation illustrates the mechanism; it is not a current bank offer or a forecast.
Actual deposit disclosures can require more specific day-count and product assumptions. The CFPB’s APY calculation rules use interest earned relative to principal and the days in the term. Do not replace a bank’s disclosed APY with a rough formula when account terms differ from the simplified example.
Why a loan APR is not a universal compounding input
It is tempting to put any advertised APR into the formula above. That can mislead you. A mortgage APR can incorporate certain upfront charges, so it is not simply the nominal rate periodically applied to the outstanding loan balance. The contract interest rate, fee timing, and repayment schedule all matter.
Credit cards add another distinction. The CFPB describes credit card APR as an annual expression of the interest rate. It is not a promise that every separate card fee is included in that percentage. Check annual fees, transfer charges, and other costs independently.
Also inspect how interest accrues. Some issuers use a daily periodic rate, which the CFPB says generally comes from dividing APR by 360 or 365, depending on the issuer. Purchases, cash advances, and transfers may have different terms. A single annual figure cannot show the effect of every transaction and payment date.
Compare savings offers beyond the headline APY
APY is useful, but your net result also depends on what happens to the account. U.S. deposit disclosure requirements address items such as rate information, compounding, minimum balances, fees, and withdrawal limitations. Use those details to build a comparison you can actually apply.
For example, suppose two hypothetical accounts would earn $40 and $45 in annual interest on the same unchanged balance. If the second also charged an unavoidable $24 annual account fee, its extra $5 of interest would not cover that cost. This is simple arithmetic, not a comparison of real products.
Check whether a higher advertised yield applies to your whole balance or only a tier. Note any introductory period and what happens afterward. If the rate can change, an annualized quote does not guarantee the amount earned over the next twelve months. Taxes and inflation also affect what the resulting money can buy.
A practical APR vs APY comparison checklist
Before using a rate in a decision, collect the same information for each comparable offer. Save the dated disclosure so you can check the assumptions rather than relying on an advertisement alone.
- Identify the product, currency, balance or loan amount, and comparison period.
- Record the exact rate label and whether the rate can change.
- List fees separately and note which are included in the disclosed rate.
- Check compounding, payment timing, withdrawal rules, and early-exit costs.
- Compare expected dollar costs or interest under the same realistic scenario.
The same habit helps when assessing other financial percentages. Desinance’s guide to the ETF bid-ask spread explains a different cost that can disappear behind a headline figure. For APR and APY, the useful question is similarly concrete: what does this percentage measure, and what will the relevant terms do to the dollars involved?
