Additional Payment Mortgage Calculator

Paying off your mortgage may seem like a far-off goal, but you have the power to make it happen sooner. By paying extra toward your principal balance, you can cut the total interest you owe and speed up your mortgage payoff timeline. This early mortgage payoff calculator shows how strategic additional payments can shift your mortgage payoff plan into high gear, saving you time and money.

Why make additional mortgage payments?

Even modest extra payments can add up to major savings over the life of your loan. By paying more than your monthly requirement, you chip away at the principal faster and reduce the total interest you owe. Whether you want to reduce your interest rate costs or build home equity faster, putting more toward your mortgage payment can deliver long-term benefits.

How extra payments help you save

Let’s zoom in on an amortization schedule for mortgages (with extra payments). Each monthly payment is split between your loan amount (principal) and interest. When you make an extra payment, that money typically goes directly toward the principal balance. Since interest is calculated based on the remaining principal, paying it down faster reduces how much interest you owe over time.

How additional payments accelerate your payoff

The more you lower your principal balance, the faster your loan amortizes, meaning less of each payment goes toward interest. Instead, a larger portion of each monthly payment goes toward the principal—allowing you to pay off your mortgage ahead of schedule. Try out our mortgage calculator with additional principal payments to visualize how quickly you could pay off your loan.

How it works

Ready to see the savings in action? Here's how to calculate your mortgage with extra payments:

  1. Enter your loan amount, loan term, interest rate and loan start date into the calculator.
  2. Head to the “Pay Off Loan Faster” section.
  3. Plug in different payment strategies and see how much you could save by:
    • Adding a set amount to your monthly payments
    • Making a one-time lump sum payment
    • Paying extra once a year

The calculator will show how much you could save on interest and how much sooner you could be mortgage-free.

What counts as an additional payment?

An additional mortgage payment is exactly what it sounds like—any amount you contribute beyond your regular bill. Fortunately, extra principal payments can be made in lots of different ways, like:

  • A one-time lump sum from a bonus or tax refund
  • A mid-month mini payment
  • Regular contributions added to each monthly payment

Just be sure your lender applies the extra funds to your principal, not toward future payments. Remember, to cut down your future interest costs, you need to pay down the principal.

Recurring vs. one-time contributions

Both recurring and one-time contributions are solid strategies—mix and match them however you like to pay off your mortgage ahead of schedule.

  • Recurring payments, like rounding up the dollar amount or switching to biweekly payments, create steady progress.
  • One-time payments from windfalls (e.g., a tax refund, bonus or inheritance) can make an immediate impact.

Using both methods can give you the most bang for your buck. Want to compare results? Test out extra payments on our mortgage calculator to see which strategy works best for your goals and budget.

Strategies to maximize savings

Use a three-pronged additional payment plan to help slash your interest and fast-track your mortgage payoff.

Biweekly payments

Switch from a monthly payment to a biweekly payment by splitting your bill in half and paying every two weeks. That results in one extra full payment each year—often applied directly to your principal balance. This can trim years off your mortgage.

Annual lump sums

Use bonuses, tax returns or other windfalls to make a one-time additional payment. You’ll lower your principal balance and reduce future interest without shaking up your monthly budget.

Round up monthly payments

Try rounding up your payment to beef up your monthly contributions. If your mortgage payment is $1,745, round up to $1,800 or $2,000. That small bump can lead to major savings over the life of your loan.

PRO TIP

When cleaning up your monthly budget and cutting out unnecessary costs (hello, streaming service you never use), you can redirect the amount you save toward extra mortgage payments. Remember, every extra payment helps you reach payoff day faster.

Next steps

You don’t have to overhaul your budget to make good progress. Even small changes—like rounding up or using a tax refund—can accelerate your payoff date without too much sweat off your back.

Talk to a Mortgage Specialist

No homeowner’s financial situation is cookie cutter. A mortgage specialist can help you decide whether to focus on interest savings, freeing up cash flow or paying off your loan sooner.

Check your lender’s prepayment policy

Some lenders apply extra payments to future installments, not the principal—and others charge prepayment penalties. Before you make additional payments, double check that they go toward the principal and won’t trigger any prepayment penalties.

Additional Payment Mortgage Calculator FAQs

  • In most cases, yes—just make sure you designate the extra amount for principal only. Always check with your lender to be sure.

  • Most modern loans don’t include prepayment penalties, but older or investment property mortgages might. Double-check your loan terms before making extra payments.

  • It depends. Paying off your mortgage offers guaranteed savings, while investing may come with higher returns and more risk. Many homeowners choose a mix of both, but a financial advisor can help you navigate those waters.

  • Even small, consistent additional payments can shorten your loan by years. Our Additional Payment Mortgage Calculator (aka interest savings calculator) estimates how fast you can finish your mortgage—and how much you could save in interest along the way.

Explore additional tools and resources

Find the support you need to understand your options and plan the next step.