Interest saved by making extra loan payments
Last reviewed: May 2026
An extra payment calculator shows how additional principal payments — whether monthly, annually, or one-time — accelerate your loan payoff and reduce total interest. Even small extra payments can save tens of thousands of dollars because they reduce the principal balance that accrues interest every month. On a $350,000 mortgage at 7%, adding just $200/month to your payment saves over $100,000 in interest and pays off the loan 7 years early.1
| Extra Payment | $350K at 7%, 30yr | Interest Saved | Years Saved | New Payoff |
|---|---|---|---|---|
| $0 (standard) | $2,329/mo | — | — | 30 years |
| +$100/mo | $2,429/mo | $62,000 | 4.2 years | 25.8 years |
| +$200/mo | $2,529/mo | $106,000 | 7.1 years | 22.9 years |
| +$500/mo | $2,829/mo | $196,000 | 12.8 years | 17.2 years |
| +1 extra/yr | $2,523/mo avg | $72,000 | 4.8 years | 25.2 years |
Amortized loans front-load interest — early payments are mostly interest, with little going to principal. A $2,329 payment on a $350K loan at 7% puts only $288 toward principal in month 1, with $2,041 going to interest. An extra $200 in month 1 nearly doubles the principal reduction, and that $200 never accrues interest again for the remaining 29+ years. The earlier you make extra payments, the more powerful the compound savings. Extra payments in year 1 save far more than the same payments in year 20.2
Biweekly payments: Pay half your monthly payment every 2 weeks (26 half-payments = 13 full payments per year instead of 12). This naturally adds one extra payment annually. Annual lump sum: Apply your tax refund or bonus to principal once a year. Round up: Round your $2,329 payment to $2,400 — the extra $71/month saves $35,000+ in interest. Redirect freed-up cash: When you pay off a car loan, redirect that payment to your mortgage instead of absorbing it into lifestyle spending.3
Extra mortgage payments may not be optimal if: (1) you have higher-interest debt (credit cards at 20% should be paid first), (2) you haven't maxed tax-advantaged retirement accounts (employer 401(k) match is a guaranteed 50–100% return), (3) you lack an emergency fund (3–6 months of expenses), or (4) your mortgage rate is below 4–5% and you could invest at higher expected returns. The math: paying extra on a 3.5% mortgage saves 3.5%, while investing in index funds historically returns 7–10%. Order of priority: emergency fund → high-interest debt → 401(k) match → extra mortgage payments or investing.4
Making extra payments on your mortgage is one of the most reliable ways to build wealth and save tens of thousands in interest over the life of a loan. On a $350,000 30-year mortgage at 7%, the scheduled total interest over the full term is approximately $488,000 — more than the original loan amount. Adding just $200 per month in extra principal payments reduces the total interest to approximately $340,000 (saving $148,000) and shortens the loan by roughly 7 years. The savings are so dramatic because early in a mortgage, the vast majority of each payment goes toward interest rather than principal — on the loan above, the first monthly payment of $2,329 allocates only $288 toward principal and $2,041 toward interest. Every extra dollar applied directly to principal shifts the amortization schedule forward, reducing the interest charged in every subsequent month.
| Extra Payment Strategy | Monthly Extra | Annual Extra | Interest Saved | Years Saved |
|---|---|---|---|---|
| No extra payments | $0 | $0 | $0 | 0 |
| $100/month extra | $100 | $1,200 | ~$86,000 | ~4.5 years |
| $200/month extra | $200 | $2,400 | ~$148,000 | ~7 years |
| $500/month extra | $500 | $6,000 | ~$240,000 | ~12 years |
| One extra payment/year | ~$194 | $2,329 | ~$120,000 | ~5.5 years |
| Biweekly payments | ~$97 | $1,165 | ~$70,000 | ~4 years |
All figures based on a $350,000 loan at 7% over 30 years. Actual savings depend on the specific loan terms and when extra payments begin.
Biweekly payments involve making half your monthly mortgage payment every two weeks instead of one full payment per month. Because there are 52 weeks in a year, you make 26 half-payments (equivalent to 13 full payments) rather than 12 monthly payments — the extra payment per year automatically reduces principal faster. On a $350,000 loan at 7%, biweekly payments save approximately $70,000 in interest and pay off the loan roughly 4 years early with no change to your per-payment amount. Many mortgage servicers offer biweekly payment programs, though some charge setup or monthly fees ($2-$5/month) that reduce the savings. You can achieve the same result for free by dividing your monthly payment by 12 and adding that amount as extra principal each month — this adds one full extra payment per year without needing a formal biweekly program.
Despite the appeal of mortgage payoff acceleration, extra payments are not always the optimal financial choice. If your mortgage rate is below your expected investment return (historically, stock market returns average 8-10%), the mathematical advantage favors investing rather than prepaying. A dollar that saves 4% in mortgage interest could instead earn 8% in the market, making investing twice as valuable financially. Higher-priority uses for extra cash include paying off high-interest debt first (credit cards at 20-25% should always be eliminated before extra mortgage payments at 3-7%), building an emergency fund (3-6 months of expenses protects against the irony of being house-rich and cash-poor), maximizing employer 401(k) match (a 50-100% immediate return that no mortgage prepayment can match), and funding Roth IRA contributions (which grow tax-free and provide long-term flexibility). The best approach for most borrowers is sequential: eliminate high-interest debt, build emergency reserves, capture employer match, then split additional funds between mortgage acceleration and investment accounts based on their relative rates. For related mortgage tools, see our Mortgage Calculator and Refinance Calculator.
The mortgage interest deduction interacts with extra payment strategies in important ways. Because extra payments reduce the outstanding principal faster, they also reduce the amount of deductible mortgage interest in future years. For itemizers, this means the true after-tax cost of the mortgage is lower than the stated rate — a 7% mortgage for someone in the 24% federal tax bracket has an effective after-tax rate of approximately 5.3% if they itemize deductions. However, since the 2017 TCJA increased the standard deduction to $14,600 single / $29,200 married (2024), approximately 90% of taxpayers now take the standard deduction rather than itemizing, making the mortgage interest deduction irrelevant for most borrowers. If you do not itemize, the full stated mortgage rate is your true cost, making extra payments relatively more attractive. The tax benefit of mortgage interest should be calculated on a marginal basis — only the interest that pushes your total itemized deductions above the standard deduction provides actual tax savings.
The extra payment strategy applies to any amortizing loan. Auto loans benefit significantly from extra payments because they are typically shorter-term with higher rates — adding $100/month extra on a $30,000 5-year auto loan at 6.5% saves approximately $750 in interest and pays off the loan 8 months early. Student loan extra payments should target the highest-rate loans first (particularly private student loans at 7-12%) while maintaining minimum payments on lower-rate federal loans. Credit card accelerated payments produce the highest returns because interest rates of 20-30% mean every extra dollar saves $0.20-$0.30 annually. Personal loan extra payments follow the same amortization math as mortgages — early in the loan, more of each payment goes to interest, so extra payments early in the term save disproportionately more. Always verify that your lender applies extra payments to principal reduction rather than advancing the due date (which does not save interest), and confirm there are no prepayment penalties before making extra payments.
→ Start small. Even $50–100/month makes a meaningful difference over 30 years. You don't need to make huge extra payments to see results.
→ Confirm principal application. Tell your lender to apply extra amounts to principal, not advance future payments.
→ Prioritize higher-rate debts first. Extra mortgage payments at 3.5% save less than paying off a credit card at 22%. Use our Debt Avalanche Calculator to optimize.
→ Use windfalls wisely. Apply tax refunds, bonuses, and gift money to principal for the biggest impact.
See also: Mortgage Calculator · Amortization Table · Refinance Calculator · 15 vs 30 Year
→ Specify payments toward principal only. When making extra payments, tell your lender to apply the extra to principal — not to advance the due date. Some lenders apply overpayments to future payments by default, which doesn't reduce interest.
→ Start extra payments early for maximum impact. A $200/month extra payment in year 1 saves far more interest than the same payment starting in year 15. Early principal reduction compounds over the entire remaining term.
→ Compare extra payments vs investing. If your mortgage is 3.5% and you can earn 8% investing, the math favors investing. But if your mortgage is 7%, paying it down offers a guaranteed 7% return. Our Compound Interest Calculator helps model this.
→ Use the debt avalanche strategy. If you have multiple debts, direct extra payments to the highest-rate debt first. A 22% credit card should be paid off before extra mortgage payments at 6%. See our Debt Snowball Calculator.
See also: Mortgage Payoff · Loan Calculator · Debt Snowball · Amortization Table