Introduction
Making extra payments on your mortgage can save you thousands of dollars in interest and help you pay off your home years earlier. Our Mortgage Extra Payment Calculator shows you exactly how much time and money you can save by putting additional money toward your loan each month, year, or as a one-time lump sum. Simply enter your loan details — like your balance, interest rate, and loan term — along with the extra amount you plan to pay. The calculator will compare your current payoff schedule to your new one, so you can see the real impact of every extra dollar. Whether you want to be debt-free sooner or just reduce the total cost of your mortgage, this tool makes it easy to plan your next move.
How to Use Our Mortgage Extra Payment Calculator
Enter your mortgage details and choose a repayment strategy to see how much interest you can save and how many years you can cut off your loan. The calculator shows your total savings, new payoff date, and a full amortization schedule.
Input Mode: Choose between two tabs at the top. Select "I Know My Original Loan Details" if you have your full loan info from closing, or select "I Only Know My Current Balance" if you just want to work with what you owe right now.
Home Price: Enter the total price you paid for your home. This is used along with your down payment to figure out your original loan amount.
Down Payment: Enter the amount of money you put down when you bought the home. The calculator subtracts this from the home price to find your loan amount.
Loan Amount: This field auto-fills based on your home price minus your down payment. You can also type in a number yourself if you want to override it.
Original Loan Term: Pick the length of your mortgage from the dropdown. Options include 10, 15, 20, 25, or 30 years.
Annual Interest Rate: Enter the yearly interest rate on your mortgage. For example, type 6.5 if your rate is 6.5%. If you're unsure how your rate translates to actual earnings on savings, our APY Calculator can help you compare annual percentage yields.
Remaining Term: Enter how many years and months you still have left on your loan. This helps the calculator figure out your current balance.
Current Remaining Balance (Mode B): If you chose the second tab, enter the amount you still owe on your mortgage today.
Current Monthly Payment (Mode B): Enter your current monthly payment for principal and interest only. Do not include taxes or insurance.
Repayment Strategy: Pick how you want to pay off your mortgage faster. Choose "Extra Payments" to add monthly, yearly, or one-time payments. Choose "Biweekly Payments" to split your payment in half and pay every two weeks, which gives you one extra full payment per year. Choose "Lump Sum Payoff" to see the total needed to pay off your loan right now. Choose "Normal Repayment" to see your baseline schedule with no changes.
Extra Monthly Payment: Enter the extra dollar amount you want to add to your mortgage payment each month on top of your regular payment.
Extra Annual Payment: Enter a lump sum you plan to pay once a year. This amount is applied each January.
One-Time Extra Payment: Enter a single extra payment you want to make right away. This is applied at the start of the calculation.
Compare With Alternative Term: Check this box and pick a loan term from the dropdown to see how refinancing to a shorter term (such as 10, 15, or 20 years) would compare to your current strategy in total cost and interest paid.
Mortgage Extra Payment Calculator
Making extra payments on your mortgage is one of the simplest ways to save money and pay off your home faster. Every dollar you pay above your required monthly payment goes straight toward reducing your loan balance, which means you pay less interest over the life of the loan. Even small extra payments can add up to tens of thousands of dollars in savings. For a focused view of your payoff timeline, you can also use our Mortgage Payoff Calculator.
How Extra Mortgage Payments Work
Your regular mortgage payment is split into two parts: principal and interest. In the early years of a mortgage, most of your payment goes toward interest rather than paying down what you actually owe. When you make an extra payment, that money reduces your principal balance right away. A lower balance means less interest is charged the next month, which means more of your regular payment goes toward principal too. This creates a snowball effect that speeds up your payoff timeline.
Types of Extra Payment Strategies
Extra monthly payments are amounts you add on top of your regular payment each month. For example, adding $200 per month to a $320,000 loan at 6.5% interest can save you over $100,000 in interest and cut years off your mortgage. Extra annual payments are lump sums you pay once a year, perhaps from a tax refund or bonus. One-time payments are single large payments made from savings, an inheritance, or another windfall.
Biweekly payments are another popular strategy. Instead of making one full payment per month, you pay half your monthly amount every two weeks. Since there are 52 weeks in a year, this results in 26 half-payments, or 13 full payments per year instead of 12. That one extra payment each year can shave several years off a 30-year mortgage.
Extra Payments vs. Refinancing
This calculator also lets you compare extra payments against refinancing to a shorter loan term, such as a 15-year mortgage. Refinancing typically gives you a lower interest rate and a guaranteed shorter payoff date, but it comes with closing costs and a higher required monthly payment. Extra payments give you flexibility — you can stop making them if money gets tight without risking default. Both approaches save you interest, so the right choice depends on your financial situation and how disciplined you are with payments.
If you're also evaluating other major loans, such as a vehicle purchase, our Auto Loan Calculator can help you understand how extra payments on a car loan compare to focusing those dollars on your mortgage instead.
Important Things to Know
Before making extra payments, check with your lender to confirm there are no prepayment penalties on your loan. Most modern mortgages do not have them, but some older or specialized loans might. Also make sure your lender applies extra payments to your principal balance and not toward future scheduled payments — you may need to specify this when you submit payment.
Financial experts generally recommend paying off higher-interest debt like credit cards before putting extra money toward your mortgage. You should also have an emergency fund covering three to six months of expenses. Once those basics are covered, extra mortgage payments can be a smart, low-risk way to build equity and reach debt-free homeownership sooner. If you're weighing whether to invest your extra cash instead, tools like our Dividend Calculator and Coast FIRE Calculator can help you compare the potential returns of investing versus the guaranteed savings of paying down your mortgage. You might also check your potential investment income with our Dividend Yield Calculator to see if your portfolio returns outpace your mortgage interest rate. Understanding metrics like your property's cap rate can also help you make smarter decisions if you own rental real estate and are deciding where to allocate extra funds.