Mortgage Payoff Calculator
Find out how much faster you'll pay off your mortgage and how much interest you'll save by adding extra to each monthly payment.
Example
On a $300,000 balance at 6% with 30 years remaining, the required payment is $1,798.65/mo. Adding an extra $200/mo (paying $1,998.65) pays the loan off in about 23 yrs 3 mos instead of 30 years.
That cuts roughly 81 months off the term and saves about $91,173 in interest ($347,515 down to $256,341).
How it works
Enter your current balance, interest rate, remaining term and an extra monthly amount. The tool computes your required payment, then simulates payoff with and without the extra to show time and interest saved.
Good to know
This Mortgage Payoff Calculator estimates how a fixed extra amount added to every monthly payment changes the life of your loan. You enter your current balance, interest rate (APR), the number of years left on the term, and the extra dollars you'd pay each month; it then derives your required (base) payment and simulates the amortization both with and without the overpayment. It's aimed at homeowners with a fixed-rate mortgage who want to see, in concrete numbers, whether prepaying is worth it.
Reach for it when you're deciding what to do with spare cash flow, a raise, or a budget surplus, and you want to compare "pay extra on the mortgage" against keeping the status quo. It's also handy for sanity-checking a number you have in mind, such as rounding your payment up to the next hundred, before you commit to it month after month.
To read the result, look at the four headline figures: your base monthly payment, your new (higher) payment, the time saved, and the interest saved. The two bars and the scenario table line the loans up side by side, so you can see total interest drop from the "no extra payment" row to the "with extra payment" row. The interest-saved figure is cumulative over the whole loan, not a yearly amount, so it will look large even for a modest monthly add-on.
One practical caveat: the estimate assumes a constant rate, that you start the extra payment now, and that every extra dollar is applied to principal each month. It excludes property taxes, insurance, and escrow, so the payment shown is principal-and-interest only and will be smaller than the total your servicer collects. Confirm your loan has no prepayment penalty and instruct your servicer to apply overpayments to principal, otherwise the real savings can fall short of the projection.
Frequently asked questions
Does an extra payment always save interest?
Yes, as long as your loan has no prepayment penalty. Any amount paid above the required payment goes straight to principal, which lowers the balance interest is charged on, shortening the term and reducing total interest.
Is the extra amount applied to principal automatically?
Not always. Many servicers apply overpayments to the next month's payment or to escrow unless you specify 'apply to principal.' This calculator assumes the full extra amount reduces principal every month.
Is my data uploaded anywhere?
No — this calculator runs entirely in your browser; nothing is uploaded.
Is this financial advice?
No. These are educational estimates — consult a qualified financial professional before making decisions.
People also ask
How much extra should I pay on my mortgage each month?
There is no single correct amount; the calculator lets you test any figure to see its effect on payoff time and total interest. Common approaches people model include rounding the payment up to a whole number, adding a fixed amount like $100 or $200, or contributing the equivalent of one extra payment per year.
Is it better to make extra mortgage payments or invest the money instead?
It depends on your mortgage rate compared with the after-tax return you expect from investing, plus your tolerance for risk and need for liquidity. Prepaying gives a guaranteed return equal to your interest rate, while investing carries both higher potential upside and the possibility of loss.
What is the difference between a base payment and an extra payment?
The base (required) payment is the fixed amount the lender requires each month to pay off the loan over its full term, covering principal and interest. An extra payment is anything you add on top, which this tool assumes goes entirely toward reducing the principal balance.
Does paying extra on my mortgage lower my monthly payment?
No. On a standard fixed-rate mortgage, extra principal payments shorten the term and reduce total interest but do not lower the required monthly amount. The payment stays the same unless you formally recast or refinance the loan.
What is a mortgage prepayment penalty?
It is a fee some lenders charge if you pay off or pay down your loan ahead of schedule, intended to offset the interest they would otherwise have collected. Many modern loans have no such penalty, but you should check your loan documents before prepaying, since this calculator assumes none applies.
Why is the interest saved so much larger than the extra I pay each month?
Because the savings are cumulative across the entire remaining loan, and each extra dollar reduces the balance that all future interest is charged on. Small monthly amounts compound into large totals over many years on a long-term loan.
Does this calculator include property taxes and insurance?
No. It calculates principal and interest only and explicitly excludes taxes, insurance, and escrow. Your actual monthly payment to a servicer will typically be higher because it bundles those items in.
How does making one extra mortgage payment a year affect the loan?
Spreading one extra payment across the year, or making a lump annual payment, reduces principal faster and can shave years off a long mortgage. You can approximate this in the tool by entering one-twelfth of your monthly payment as the extra monthly amount.
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