True Borrowing Cost
Last reviewed: May 2026
The Annual Percentage Rate is the federally mandated metric for comparing loan costs, required under the Truth in Lending Act (TILA) since 1968.[1] It levels the playing field by rolling fees into the rate, making it easier to compare offers from different lenders. However, APR has limitations: it assumes you keep the loan for the full term, and it does not include all costs (like title insurance). Use the Mortgage Payment Calculator for monthly payment estimates.
| Lender | Rate | Fees/Points | APR | Monthly Pmt | Total Cost |
|---|---|---|---|---|---|
| A (low fees) | 6.75% | $1,500 | 6.79% | $1,946 | $701,960 |
| B (1 point) | 6.50% | $4,500 | 6.61% | $1,896 | $687,160 |
| C (high fees) | 6.25% | $9,000 | 6.48% | $1,847 | $673,920 |
| D (no fees) | 7.00% | $0 | 7.00% | $1,996 | $718,560 |
APR calculation is more complex than simply adding fees to the interest rate. The federal Truth in Lending Act requires lenders to calculate APR by finding the discount rate that equates the present value of all scheduled payments to the net loan proceeds (the amount actually received after fees). This is essentially an internal rate of return (IRR) calculation on the loan cash flows. For a $300,000 mortgage at 6.5% with $4,500 in fees, the borrower receives $295,500 but makes payments based on $300,000 at 6.5%. The APR reflects the effective rate on the $295,500 actually received — approximately 6.63%. The mathematical difference between the stated rate and APR depends on both the fee amount and the loan term: the same fees spread over 30 years have a smaller APR impact than over 15 years because the cost is amortized over more payments.
| Loan Type | Typical Rate | Common Fees | Typical APR | APR Spread |
|---|---|---|---|---|
| 30-year mortgage | 6.5% | $3,000–$8,000 | 6.6–6.8% | 0.1–0.3% |
| 15-year mortgage | 5.8% | $3,000–$8,000 | 6.0–6.3% | 0.2–0.5% |
| Auto loan (new) | 5.5% | $0–$500 | 5.5–5.7% | 0–0.2% |
| Personal loan | 10% | 1–8% origination | 11–18% | 1–8% |
| Credit card | 22% | $0 (annual fee separate) | 22% | 0% |
Discount points allow borrowers to pay upfront to reduce their interest rate — typically 1 point (1% of the loan amount) reduces the rate by 0.25%. On a $400,000 loan, 1 point costs $4,000 and might lower the rate from 6.75% to 6.50%, saving approximately $67 per month. The break-even period is $4,000 ÷ $67 = 60 months (5 years). If you plan to stay in the home longer than 5 years, paying points is mathematically advantageous. APR captures this trade-off: the points increase the APR relative to the reduced rate because the upfront cost is factored in. A loan at 6.50% with 1 point might have the same APR as a loan at 6.75% with no points — making the two offers effectively equivalent over the full term. However, APR assumes you keep the loan for the full 30 years. If you refinance or move sooner, the no-points option may cost less overall because the point expense was not fully recovered. Use our Mortgage Points Calculator for detailed break-even analysis.
Despite being the federally mandated comparison metric, APR has significant limitations. It assumes you hold the loan for the entire term — a false assumption for most borrowers, since the average mortgage is refinanced or paid off within 7 to 10 years. For a borrower who refinances after 5 years, a loan with higher fees and lower rate might cost more than one with lower fees and higher rate, even though the APR suggests otherwise. APR also excludes several real costs: title insurance (which can exceed $2,000), home inspection fees, property taxes, homeowners insurance, and private mortgage insurance (PMI). Two loans with identical APRs can have meaningfully different total costs when these excluded items are considered.
Additionally, APR does not account for the time value of money from the borrower's perspective. Paying $5,000 in upfront fees versus paying higher monthly interest distributes costs differently across time. If you could invest that $5,000 at a rate exceeding the interest rate differential, keeping the cash and accepting the higher rate is financially superior. This opportunity cost calculation is invisible in the APR metric. For a comprehensive cost comparison that includes all fees, see our Closing Cost Calculator.
When comparing loan offers, start with APR as the baseline comparison but do not stop there. Request a Loan Estimate (LE) from each lender — this standardized form, required within three business days of application, breaks down every fee and shows the APR calculation. Compare the LE documents side by side, paying particular attention to Section A (origination charges), Section B (services the lender selects), and Section J (total closing costs). If two lenders show similar APRs but different fee structures, the lower-fee option is usually better for borrowers who may refinance or move within 10 years. For fixed-rate mortgages, APR comparison is most reliable. For adjustable-rate mortgages, APR is calculated using the initial rate for the fixed period and then the fully-indexed rate for the remaining term, making it a blend that may not reflect your actual experience if rates change differently than the index assumption.
APR and APY serve different purposes and are used in different contexts. APR appears on the borrowing side: mortgages, auto loans, personal loans, and credit cards. It represents cost to the borrower excluding the effect of compounding within the year. APY appears on the savings side: savings accounts, CDs, and money market accounts. It includes the effect of compounding, making it slightly higher than the nominal rate. A savings account at 4.5% APR compounded daily has an APY of approximately 4.60%. The difference matters: when comparing savings options, APY is the correct metric because it reflects the actual earnings you receive. When comparing loans, APR is mandated for disclosure because it includes fees. Converting between them requires knowing the compounding frequency: APY = (1 + APR/n)^n - 1, where n is the number of compounding periods per year. For savings comparisons, see our Savings Growth Calculator.
Credit card APR functions differently from loan APR because credit cards use a revolving balance with daily compounding. The daily periodic rate is the APR divided by 365 — at a 22% APR, the daily rate is 0.0603%. Interest accrues daily on the average daily balance, meaning a $5,000 balance generates approximately $3.01 in interest per day ($1,100 per year). Paying only the minimum payment (typically 1% to 2% of the balance plus interest) extends payoff dramatically: a $5,000 balance at 22% with minimum payments takes approximately 14 years and costs $6,300 in interest — more than the original balance. Credit cards also carry multiple APR tiers: purchase APR, cash advance APR (typically 5-10 points higher), balance transfer APR, and penalty APR (up to 29.99% triggered by late payments). The penalty APR can apply retroactively to the existing balance with some issuers, making timely payments critical. For credit card payoff strategies, see our Credit Card Payoff Calculator.
Variable-rate loans tie the APR to a benchmark index — commonly the prime rate, SOFR (Secured Overnight Financing Rate), or a Treasury yield — plus a fixed margin. When the benchmark rises, the APR increases; when it falls, the APR decreases. HELOCs, adjustable-rate mortgages, and most credit cards use variable rates. The risk is asymmetric: rate increases raise your payment immediately, while rate decreases provide relief only after they happen. On a $200,000 HELOC at prime + 1% with a prime rate of 8.5%, the APR is 9.5%. If the prime rate rises to 10%, the APR becomes 11%, increasing the monthly interest cost by roughly $250. Rate caps limit the maximum increase per adjustment period and over the loan life, but caps on HELOCs are typically high — often 18% to 21%. Understanding the fully indexed rate (index + margin) and the worst-case cap scenario is essential before committing to any variable-rate product.
→ Always compare APR, not just rate. A lower rate with high fees can cost more overall.[1]
→ Factor in your time horizon. Points only pay off if you keep the loan long enough to break even.
→ Get Loan Estimates from 3+ lenders. The standardized form makes APR comparison easy.[2]
→ APR matters most for mortgages. For short-term loans, total fees matter more than APR.
See also: Interest Rate · Mortgage Payment · Loan Calculator · Refinance