One extra payment cuts years off your mortgage, but the exact savings depend on your loan size, interest rate, and where you are in the payoff
A single extra mortgage payment typically saves between one and three years of payments, depending on your loan balance and interest rate. The higher your interest rate and the earlier you make the payment, the more time you cut off the end of your loan. On a $300,000 mortgage at 6% interest, one extra payment made early in the loan saves roughly two to three years. On the same loan at 3% interest, the savings drop to about one to two years.
The reason the savings vary so much is that most of your early payments go toward interest, not the loan balance itself. When you make an extra payment early, almost all of it reduces what you owe, which means less interest compounds on that smaller balance for the rest of the loan. Later in the loan, when more of each payment already goes to principal, an extra payment saves less time because you are already paying down the balance faster.
The real value of one extra payment is not just the time saved — it is also the interest you do not pay. On that same $300,000 loan at 6%, one extra payment made in year one might save $20,000 to $30,000 in total interest over the life of the loan. At 3%, the savings might be $8,000 to $12,000. These numbers shift based on your exact rate and loan term.
Key Takeaways
- One extra payment made early in your mortgage can cut one to three years off your loan, with larger savings at higher interest rates.
- The same extra payment made late in the loan saves much less time because you are already paying down principal faster.
- An extra payment saves money in two ways: it shortens the loan and it reduces the total interest you pay over the life of the mortgage.
- You can calculate your specific savings by using your loan balance, interest rate, and remaining term in a mortgage payoff calculator.
Why timing matters more than the payment amount
The month you make an extra payment changes the outcome dramatically. If you make one extra payment in month one of a 30-year loan, you are reducing the balance that interest will compound on for 360 months. If you make that same payment in month 300, you have only 60 months left for the compounding to work in your favor.
This is why the first extra payment saves the most time and interest. Each month you wait, the benefit shrinks. By the time you reach the final years of your mortgage, an extra payment might shorten your loan by only a few weeks rather than years.
The interest rate on your loan amplifies this timing effect. At 7% interest, the compounding works harder against you early on, so an extra early payment saves more. At 2.5% interest, the compounding effect is weaker, so the time savings are smaller — but they still exist.
How to calculate your specific savings
You do not need to guess. Most mortgage lenders provide an amortization schedule — a month-by-month breakdown of how much of each payment goes to principal and interest. Ask your lender for this document, or request it from your loan servicer (the company that collects your payments).
With that schedule in hand, you can see exactly how much principal you owe at any point. Then use a mortgage payoff calculator (search "mortgage payoff calculator" in any browser) and enter three numbers: your current loan balance, your interest rate, and your remaining term in months. Run the calculation once as-is, then run it again with a lower balance (reduced by one payment's worth of principal). The difference in payoff date is your savings.
Many online calculators also show total interest paid under each scenario, which is often more meaningful than the time saved. Seeing that one extra payment saves $15,000 in interest may motivate you more than knowing it saves 18 months.
The difference between one payment and a pattern of extra payments
One extra payment is a single action. A pattern of extra payments — making an extra payment every year, or every month, or every quarter — compounds the benefit. If one extra payment saves you two years, making one extra payment per year for five years does not save you ten years. Instead, it saves you closer to four to five years, because each subsequent payment has less balance to work with.
Still, the cumulative effect is powerful. Someone who makes one extra payment every year for 15 years will pay off a 30-year mortgage in roughly 20 to 22 years instead, depending on the interest rate. They will also save tens of thousands in interest.
The key difference is consistency. One extra payment is a one-time event. If you can only afford one, make it as early as possible. If you can make extra payments regularly, the earlier you start, the more dramatic the total effect.
What happens to your monthly payment when you pay off early
Making extra payments does not lower your regular monthly payment. Your lender will continue to expect the same amount each month. The extra payment straightforward reduces your loan balance faster, which means you reach zero sooner.
Some loans allow you to request a payment recalculation after you have paid down a significant amount of principal. This recalculates your monthly payment based on the new, lower balance and remaining term. Not all lenders offer this, and some charge a fee. Check your loan documents or call your servicer to ask whether recalculation is available.
In most cases, you will keep making the same monthly payment until the loan is paid off. The extra payment is separate — it goes directly to principal and does not change your regular obligation.
When one extra payment makes the most sense
An extra payment is most valuable if you have a high interest rate (5% or above), you are early in the loan (within the first ten years), and you have the cash without borrowing or cutting essential spending. At lower interest rates (3% or below), the time and interest savings are smaller, so the decision depends more on your other financial priorities.
If you have high-interest debt — credit cards, personal loans, or car loans — paying down those first usually saves more money than an extra mortgage payment. Mortgage interest is tax-deductible for many people, which lowers the real cost of the loan. Credit card interest is not deductible, which makes it more expensive in real terms.
If you have no emergency fund or are carrying consumer debt, building savings or paying down that debt first is usually wiser than accelerating your mortgage payoff. Once those are handled, extra mortgage payments become a reasonable choice.
The tax and investment angle
Mortgage interest is tax-deductible if you itemize deductions on your tax return (rather than taking the standard deduction). This means the real cost of your mortgage is lower than the interest rate suggests. If you have a 6% mortgage and you are in the 24% tax bracket, the after-tax cost of that interest is closer to 4.56%.
Some people argue that instead of making an extra mortgage payment, you should invest that money in the stock market, which historically returns 7% to 10% per year on average. If your mortgage costs 4.56% after taxes and the market returns 8%, you come out ahead by investing. However, this assumes you will actually invest the money and stay invested through market downturns — many people do not.
The safest approach is to think about your comfort level. If paying off your mortgage faster gives you peace of mind and you can afford it without sacrificing other goals, one extra payment is a reasonable choice. If you prefer to invest or keep the cash liquid, that is also reasonable. There is no single right answer.
Frequently Asked Questions
Does making one extra payment actually save a full year?
Not always a full year — it depends on your interest rate and where you are in the loan. On a high-rate loan early on, one extra payment might save 18 to 24 months. On a low-rate loan or late in the payoff, it might save only a few months. Use a payoff calculator with your specific numbers to see the real savings.
Should I make the extra payment in a lump sum or split it across the year?
A lump sum made as early as possible saves more time and interest. If you split one payment across 12 months, you get the same total benefit but spread over time. The difference is small — maybe a few weeks of additional savings with the lump sum — so choose whichever fits your cash flow better.
What if I make an extra payment but then lose my job?
Extra payments reduce your loan balance but do not change your required monthly payment. If you lose income, you still owe the same amount each month. Make extra payments only if you have a stable income and an emergency fund. Do not stretch to make extra payments if it means you have no cushion for job loss or unexpected costs.
Can I tell my lender to explore extra money to principal instead of interest?
Yes. When you send an extra payment, include a note or call your servicer and specify that the extra amount should go to principal, not toward future payments. Some servicers explore extra money to the next month's payment by default, which does not save you as much time. Being explicit prevents that.
Is one extra payment better than refinancing to a shorter loan term?
They are different tools. One extra payment costs nothing and saves some time. Refinancing to a 15-year loan instead of 30 years raises your monthly payment significantly but cuts the payoff time in half and saves much more interest. One extra payment is a low-commitment way to test whether you can afford faster payoff. If you can handle it easily, refinancing might be the next step.