One extra payment per year cuts years off your loan and saves tens of thousands in interest
A single extra mortgage payment each year—whether you make it as a lump sum or split it across monthly payments—shortens your loan by roughly one to three years and reduces total interest paid by 5 to 10 percent, depending on your loan balance, interest rate, and how far into the loan you are. The earlier you start, the larger the savings. A payment made in year 2 saves more than the same payment made in year 20.
The math is straightforward: every dollar that goes to principal instead of interest compounds over the remaining life of the loan. On a $300,000 mortgage at 6.5 percent over 30 years, one extra $1,500 payment per year (the equivalent of one monthly payment) can save you $40,000 to $60,000 in interest and shorten the loan by 3 to 4 years. On a smaller loan or higher rate, the impact is proportionally larger.
Key Takeaways
- One extra mortgage payment per year typically saves $30,000 to $70,000 in interest over the life of the loan, depending on your loan size and rate.
- The payoff date moves up by one to four years with consistent extra payments, with the biggest impact in the first half of the loan.
- You must instruct your lender to apply extra payments to principal, not to next month's payment or escrow—this is not automatic.
- Making extra payments early in the loan saves more interest than making them late, because you are reducing the balance that future interest accrues on.
- If your mortgage rate is below 4 percent or you have high-interest debt elsewhere, the math may favor paying down other debts first.
How the savings break down by loan stage
The benefit of an extra payment is not the same in year 5 as it is in year 25. Early in the loan, most of your monthly payment goes to interest. A $1,500 payment made in year 2 might reduce interest by $800 and principal by $700. That same payment in year 25 might reduce interest by $200 and principal by $1,300—but by then, you have already paid most of the interest anyway.
On a 30-year, $300,000 mortgage at 6.5 percent: one extra payment per year starting in year 1 saves roughly $58,000 in total interest and closes the loan in year 27 instead of year 30. If you wait until year 10 to start making extra payments, the same annual payment saves roughly $28,000 and closes the loan in year 28. The difference is $30,000 in lost savings by waiting a decade.
This is why lenders encourage you to make extra payments early and why financial advisors often recommend it as a first step after building an emergency fund: the return on that money is may provide (you avoid paying interest at your mortgage rate) and it compounds backward through time.
The difference between lump-sum and monthly extra payments
You can make one extra payment as a single lump sum once a year, or you can add a small amount to your regular monthly payment. The total savings is nearly identical if the total amount is the same, but the timing matters slightly.
A lump sum of $1,500 made in January saves interest on that $1,500 for the entire year. The same $125 added to your monthly payment ($1,500 ÷ 12) saves interest gradually throughout the year. Over 30 years, the lump-sum approach saves a few hundred dollars more, but the difference is small enough that you should choose whichever method fits your cash flow. If you receive a bonus or tax refund, a lump sum is simpler. If you want to spread the cost across 12 months, add to your payment.
What matters most is that you actually make the payment and that it goes to principal. Many borrowers add $50 or $100 to their monthly payment without realizing their lender is applying it to next month's payment instead of to principal. Always confirm in writing with your lender that extra payments are being applied to reduce the loan balance.
How to instruct your lender to apply extra payments correctly
When you send an extra payment, your lender has three places it could go: toward next month's regular payment, toward your escrow account (property taxes and insurance), or toward principal. Only the third option saves you interest. The first two just shift when you pay your regular bill.
Contact your lender's payment department and ask them to set a standing instruction: "Apply all payments above the regular monthly payment amount to principal." Get a confirmation number and keep the email or letter. Some lenders allow you to set this in your online account; others require a phone call or written request.
After you make the first extra payment, log into your account or call to verify that the principal balance decreased by the amount you sent. If it did not, contact the lender immediately and ask where the money went. This is the most common mistake borrowers make—they send extra money but never confirm it was applied correctly, so they think they are building equity faster than they actually are.
When extra mortgage payments make less sense
Extra mortgage payments are not always the best use of money. If your mortgage rate is 3 percent and you have credit card debt at 18 percent, pay off the credit card first—the may provide return is much higher. If you have no emergency fund, build that before making extra mortgage payments; an emergency fund keeps you from taking on new debt when something breaks.
If your mortgage rate is below 4 percent and you have access to a tax-advantaged retirement account (401k, IRA, HSA) that you are not fully funding, the math often favors the retirement account. You get a tax deduction or tax-free growth, and you can invest the money in stocks that historically return more than your mortgage savings. A 3 percent mortgage rate versus a 7 percent stock return means the retirement account wins.
If you are planning to sell or refinance within five years, extra payments may not pay off—you will not be in the loan long enough to recoup the benefit. If you are underwater on your mortgage (owe more than the home is worth), extra payments do not help you build equity in the way they would on a home with positive equity.
The real payoff date and interest savings for common loan sizes
| Loan Amount | Interest Rate | Original Payoff | With One Extra Payment/Year | Years Saved | Interest Saved |
|---|---|---|---|---|---|
| $200,000 | 6.5% | 30 years | 27 years | 3 | $38,000–$42,000 |
| $300,000 | 6.5% | 30 years | 27 years | 3–4 | $58,000–$65,000 |
| $400,000 | 6.5% | 30 years | 27 years | 3–4 | $78,000–$88,000 |
| $300,000 | 4.0% | 30 years | 28 years | 2 | $22,000–$26,000 |
| $300,000 | 7.5% | 30 years | 26 years | 4 | $78,000–$88,000 |
These figures assume one extra payment per year applied to principal from year 1 onward. Actual savings vary based on your exact payment schedule, whether you make extra payments consistently, and whether rates or terms change (such as through refinancing). Use a mortgage calculator with an "extra payment" field to run the numbers for your specific loan.
What happens if you stop making extra payments
If you make extra payments for five years and then stop, you do not lose the benefit you already earned—the principal is already paid down. But you do lose the compounding effect of the remaining extra payments. If you made extra payments for years 1–5 and then stopped, you might save $15,000 in interest instead of $58,000. The years you did make extra payments still count.
This is why even small extra payments matter: $50 per month ($600 per year) over 30 years saves roughly $20,000 to $30,000 in interest, depending on your rate. You do not need to commit to a full extra payment to see real savings. Start with what you can afford, and increase it when your income rises or a debt is paid off.
Frequently Asked Questions
Does making one extra payment per year actually shorten the loan by one year?
No—it typically shortens the loan by one to four years depending on your rate and loan size. A higher rate or larger loan sees a bigger time reduction. The reason is that extra principal payments compound: each dollar reduces the balance that future interest accrues on, creating a cascading effect. A mortgage calculator will show you the exact payoff date for your situation.
Should I make one lump-sum payment or add to my monthly payment?
Either works, and the total savings is nearly identical. A lump sum saves a few hundred dollars more over 30 years because the money reduces interest for the full year. But if a lump sum is hard to save, adding $100–$150 per month is easier to stick with and still saves tens of thousands. Choose based on what you can actually do consistently.
What if my lender says they cannot apply extra payments to principal?
They can. This is a standard feature of every mortgage servicer. If they claim they cannot, ask to speak to a supervisor or submit a written request. If the lender still refuses, contact your state's banking regulator or the Consumer Financial Protection Bureau. You have the right to pay down principal ahead of schedule.
Is it better to pay extra on my mortgage or invest the money?
It depends on your mortgage rate and investment returns. If your mortgage is 3 percent and stocks historically return 7 percent, investing may win. If your mortgage is 7 percent and you have high-interest debt, paying the mortgage down is safer. If you are unsure, split the difference: make modest extra payments and invest the rest in a tax-advantaged account.
Can I deduct extra mortgage payments on my taxes?
No. You can only deduct the interest portion of your mortgage payment, not the principal. Extra payments reduce your interest deduction slightly over time because you are paying less interest overall. This is a minor tax effect and should not change your decision to make extra payments.