Extra payment mortgage calculator

In the mortgage industry, an extra payment and a prepayment mean the exact same thing. Both terms refer to paying off a portion of your loan's principal before the official due date to reduce your total lifetime interest. When reviewing your loan documents, you might see the term "prepayment privilege," which outlines how much extra you can pay without incurring a fee. Whether you call it an extra payment, an additional principal payment, or a prepayment, the mathematical result is identical: the money goes straight to reducing your balance, which you can track using the calculator above.

Adding an extra $100 a month directly toward your principal reduces your balance faster and can shave years off your payoff timeline because of compounding interest. On a typical 30-year mortgage, the majority of your early standard payments go toward interest, not principal. By consistently adding just $100 extra, you force the balance down early in the loan's lifecycle. Over 30 years, this relatively small budget adjustment often translates into tens of thousands of dollars saved in interest. You can use our calculator to find your exact debt-free date based on your specific loan terms.

A bi-weekly schedule accelerates your payoff because it creates 13 full payments a year instead of the standard 12. By making half your standard payment every two weeks, you naturally add one extra principal payment annually, which significantly reduces total interest and shortens your loan term. This is an excellent "set it and forget it" method, especially for homeowners who receive their paychecks bi-weekly, as the mortgage deduction naturally aligns with payday. To simulate this in our calculator, simply calculate your total monthly principal and interest payment, divide it by 12, and enter that number as a monthly prepayment.

When you make an extra payment, 100% of that money goes directly toward your principal balance instead of being split with interest. Because your balance drops instantly, less of your future standard payments will go toward interest, which accelerates your payoff date and shifts your entire amortization schedule forward. Traditional amortization schedules are heavily "front-loaded" with interest, meaning every extra dollar you pay acts as a shortcut allowing you to skip rows on that schedule. You can see a side-by-side comparison of your standard timeline versus your accelerated timeline by viewing the schedule in our calculator.

Making a lump sum principal payment—like from a tax refund or work bonus—immediately reduces your loan balance, causing all future interest to be recalculated on a much lower amount. This acts like a "mortgage snowball," permanently lowering your total interest costs and moving up your mortgage freedom date. Because mortgage interest compounds, applying surplus funds directly to your principal early in the loan has a massive impact. For example, a single $5,000 lump sum payment in your first year can save you tens of thousands of dollars over the life of a typical 30-year loan.

In most cases, you can pay off your mortgage early without any penalties. The vast majority of modern residential loans, including standard Conventional, FHA, and VA loans, do not carry prepayment penalties that charge you for paying off the loan ahead of schedule. While they are rare on standard home loans today, these penalties can still exist on certain types of non-traditional or commercial loans, usually only lasting for the first three to five years of the mortgage. You can easily confirm your early payoff freedom by checking the first page of your "Closing Disclosure" document or speaking with your loan officer.

Making extra payments will not lower your required monthly mortgage bill; instead, it shortens the total lifespan of your loan. Your monthly payment is locked in based on your original loan term, interest rate, and principal balance. When you pay extra, the bank simply brings your final payoff date closer rather than recalculating your required monthly bill. The only exception is if you request a "mortgage recast," where the lender recalculates your monthly payment based on your new, lower balance. If lowering your actual monthly payment is your main goal, refinancing to a lower interest rate is usually the best strategy.