Calculate payoff from your current mortgage balance
Most payoff calculators start from the original loan. This one starts from where you are now: the principal you still owe, your fixed interest rate, and either the months remaining or your monthly principal-and-interest payment. If you know the months left, the level payment is calculated for you. If you know your payment instead, the calculator simulates the schedule until the balance is gone. Either way it first builds a baseline with no extra payments, so every saving is measured against your real schedule.
Enter principal and interest only. Escrow for property tax and insurance, mortgage insurance and servicing fees are paid separately and do not reduce the balance, so including them would understate your payoff speed. If your payment barely covers the first month's interest, the balance would never fall, so the calculator explains that instead of inventing a payoff date.
Compare monthly, annual and one-time extra payments
You can combine three kinds of extra principal. A monthly extra is paid every month from the first payment. An annual extra, such as a bonus, is paid in a payment number you choose from 1 to 12 and every 12 payments after that. A one-time extra, such as a windfall, is paid in the payment number you choose, from 1 to 600. Each month the schedule works in a fixed order: interest accrues on the opening balance, the regular payment is applied, then the monthly extra, then any annual or one-time extra due that month. Every extra is capped at what is still owed, and nothing is charged after the loan is paid off.
See interest saved and export your payoff schedule
The results compare your current schedule with your plan: payments left, payoff month, interest from today and the final payment. Interest saved counts only the interest you would still pay from now; interest you have already paid is sunk and is not claimed as a saving. The chart shows the balance falling with and without your plan, and a table gives the same figures. The schedule lists every payment with the regular amount, the extra, interest, principal and balance, and the CSV export includes both schedules.
Find an extra payment for a target payoff month
Choose Target payoff month and enter how many months you want to be debt-free in. The calculator computes the level payment that clears your balance in that time and subtracts your current payment: the difference is the extra monthly amount you need. If your current payment already finishes in time, it reports that no extra is needed. Target mode is deliberately simple, so the annual and one-time extras are switched off while it is selected.
Worked example with precisely timed extra payments
Take a balance of $10,000 at 12% with 24 months left. The regular payment is $470.73 and, with no extras, the remaining interest is $1,297.63. Now pay $100 extra every month, $200 extra in payment 12 and every 12 payments after, and $500 extra in payment 3. Payment 3 includes the $100 and the $500, so $600 of extra principal; payment 12 includes the $100 and the $200, so $300. The loan is gone in 18 payments, the remaining interest is $947.09, and the saving is $350.54. The last payment is $544.60 because it is capped at the balance. To finish the same balance in 12 months you would need a total payment of $888.49, an extra $417.75 a month.
Monthly accrual, escrow and lender-term limitations
- Month-end model with unrounded interest. Lenders may accrue daily, round cents, or credit extra principal on a different date, so statement balances can differ slightly.
- Fixed rate and principal-and-interest only. Escrow, mortgage insurance, late fees, adjustable rates and recasting are not modelled.
- Up to 600 monthly rows. If your own payment would need more than 600 months, the calculator says it is unsupported rather than showing a partial payoff.
- Prepayment penalties are excluded from the savings. Check your contract and any limit on extra principal before paying more.
- Educational estimates, not financial advice. Paying down a mortgage is one of several uses of money.
FAQ
How much sooner can I pay off my mortgage?
It depends on the size and timing of your extra payments relative to your balance and rate. Enter them and read the payments-left figure: in the example above, $100 a month plus a yearly and a one-time extra turns 24 payments into 18.
How much interest does an extra principal payment save?
Each extra dollar of principal stops accruing interest for the rest of the loan, so earlier payments save more than later ones. The calculator measures the saving as the difference in total interest between the two full schedules, from today forward.
When are annual and one-time payments applied?
At the end of the payment number you choose, after that month's regular payment and monthly extra. An annual extra repeats every 12 payments. A payment dated after the loan is already paid off is never charged.
Should my payment include taxes and insurance?
No. Enter only the principal-and-interest part of your payment. Taxes, insurance and mortgage insurance in your escrow do not reduce the loan balance, so leave them out or the payoff will look too slow.
Can I use this for biweekly payments or prepayment penalties?
Not directly. A biweekly plan pays about one extra monthly payment a year, which you can approximate with an annual extra equal to one payment, but lenders apply biweekly payments in different ways. Prepayment penalties are not part of the calculation, so confirm the terms with your lender. To compare a general loan with fees, see the loan payment calculator with included-fee APR. Whether to prepay or invest is a separate decision covered by the mortgage versus investing calculator, and the emergency fund calculator helps you check you keep a cash buffer before putting every spare dollar into your mortgage.