Skip to Main Content

Extra mortgage payment calculator

How to use this calculator

Enter just a few details in this tool to determine how much money you might save by paying more than the minimum on your mortgage each month. 

  1. Enter the years remaining on your mortgage: This reflects how many years you still have left to pay off the loan. 
  2. Enter your original mortgage term: The total length of your loan when you first got it (30 years is most common). 
  3. Enter your original mortgage amount: The full amount you initially borrowed. 
  4. Enter your additional payment amount: How much extra money you plan to put toward your loan principal each month. You can try different amounts to see how much money you’ll save and how it affects your projected payoff date.
  5. Enter your interest rate: Input the interest rate you are currently paying here. You can compare your rate to Bankrate’s national average rates on our mortgage rate table. 
  6. Click the “calculate” button: This will show how your extra payments impact your loan payoff timeline and total interest paid.

Understanding your results

After you’ve input your information, the calculator estimates your monthly principal and interest payment and reveals the long-term impact of your extra contributions.

For example, say you are five years into a $400,000 loan with a 30-year term at 6% interest. If you were to pay an additional $100 per month toward your principal for the remaining 25 years, you would save more than $35,000 in interest. In addition, you’d pay the loan off two years and two months faster than you would making just the minimum monthly payments.

If you were able to pay even more per month, you’d see even greater benefits: An additional $150 would save you close to $50,000, with a payoff three years and one month earlier.

Even a little goes a long way over the course of a lengthy mortgage. Using this same example, paying just $25 additional per month still saves you $9,565 in interest and shortens your repayment by seven months.

Factors that can affect extra mortgage payments

Before you start applying additional payments to your mortgage, here are a few factors to consider:

  • Payment allocation: Many lenders default extra funds toward your next month’s bill, which includes interest. In order to realize the savings, be sure your lender allows additional payments to be applied only to the principal — and be sure to explicitly request it when making your payment.
  • Timing: Mortgage interest is "front-loaded," meaning your early payments are mostly interest. So extra payments toward the principal in the first years of a loan are the most powerful. For example, by paying down the principal during the first 10 years of a 30-year loan, you lower the balance you’re charged interest on for the next two decades. 
  • Prepayment penalties: Some lenders may charge a fee for early payment. Check your documents to ensure a penalty won’t wipe out your hard-earned interest savings. 
  • Other debts: If you have other pressing debts, especially with a much higher interest rate than your mortgage (such as credit card debt), it may be smarter to clear those before putting extra money toward a lower-interest mortgage. 
  • Lump-sum payments: If you receive a bonus, an inheritance or another type of windfall, you may want to make a large one-time payment rather than increased monthly payments. A mortgage recast may be a good option here. In this scenario, a lender will apply your large payment to the principal and recalculate your monthly payments for the remainder of the loan. Not all lenders offer this option, but it’s worth inquiring to see if you’re eligible.
  • Opportunity cost: Before deciding to put extra cash toward your mortgage, consider the returns you're getting anywhere your money is actually growing. If your money is earning a higher rate in the bank or in the market than you're currently paying on your mortgage, you might be better off keeping it there for now.

Next steps

Now that you’ve seen how extra payments can impact your loan, the next step is deciding if you should put that strategy into action. 

First, if you’re concerned about whether you can afford additional payments on your mortgage, consider testing your budget by setting aside the same amount in a high-yield savings account for a few months. If you don’t miss the money, you’re in a strong position to move forward. But if you find that money is tight, keeping the cash accessible may make more sense for you. 

It’s also worth checking today’s refinance rates to see how they compare to your current mortgage rate. If they’re significantly lower, you might consider refinancing into a shorter-term loan, instead of just making additional payments on your existing loan.

When you’re ready to go ahead, take a close look at your mortgage documentation to make sure your lender allows extra payments to the principal. If it’s not clear, ask, and make sure you understand exactly how to allocate the funds when you make your payment — there may be a box to check off in the online portal if you pay online, for example. 

Related calculators and resources