Mortgage payoff calculator: new payoff date, months and interest saved by extra monthly, yearly or one-time payments, or the extra to finish by a date.
Extra payments save this interest only when the servicer applies them to principal; say so with each payment.
The extra payments clear the loan in 20 years 3 months instead of 25 years, 4 years 9 months sooner, with the last payment in February 2047. They total $48,400.00 and save $68,041.94 of interest.
Loan balance: current plan and with extra payments
Current planWith extra payments
Interest left to pay
Payoff schedule with extra payments Rows: 243
No.
Date
Payment
Extra
Principal
Interest
Balance
1
Saturday, 12 December 2026
$2,225.62
$200.00
$600.62
$1,625.00
$299,399.38
2
Tuesday, 12 January 2027
$2,225.62
$200.00
$603.87
$1,621.75
$298,795.50
3
Friday, 12 February 2027
$2,225.62
$200.00
$607.15
$1,618.48
$298,188.36
4
Friday, 12 March 2027
$2,225.62
$200.00
$610.43
$1,615.19
$297,577.92
5
Monday, 12 April 2027
$2,225.62
$200.00
$613.74
$1,611.88
$296,964.18
6
Wednesday, 12 May 2027
$2,225.62
$200.00
$617.07
$1,608.56
$296,347.12
7
Saturday, 12 June 2027
$2,225.62
$200.00
$620.41
$1,605.21
$295,726.71
8
Monday, 12 July 2027
$2,225.62
$200.00
$623.77
$1,601.85
$295,102.94
9
Thursday, 12 August 2027
$2,225.62
$200.00
$627.15
$1,598.47
$294,475.79
10
Sunday, 12 September 2027
$2,225.62
$200.00
$630.54
$1,595.08
$293,845.25
11
Tuesday, 12 October 2027
$2,225.62
$200.00
$633.96
$1,591.66
$293,211.29
12
Friday, 12 November 2027
$2,225.62
$200.00
$637.39
$1,588.23
$292,573.90
How it's calculated S
Monthly rate
r=12006.5=0.00541667
Current monthly payment
M=(1+r)300−1300,000×r(1+r)300=2,025.62
Principal and interest that clear the balance in the 300 months left, with r = 0.00541667.
Current plan
interest=607,686.45−300,000=307,686.45
All payments minus the balance. 300 payments of $2,025.62.
With extra payments
interest=539,644.50−300,000=239,644.50
All payments minus the balance. 243 payments; each extra amount goes straight to principal.
Interest saved
307,686.45−239,644.50=68,041.94
About the mortgage payoff calculator
The loan is run month by month twice, once at the current payment and once with your extra payments added. Each month's interest is the balance times the annual rate ÷ 12; the payment covers that interest first, and the rest, plus any extra, reduces the principal. The interest saved is the difference between the two schedules. If you know your payment but not the term left, the term is found from the balance, rate and payment.
With the defaults, 300,000 owed at 6.5% with 25 years left, the payment is 2,025.62. Adding 200 a month ends the loan after 243 payments instead of 300, 4 years 9 months early, and saves 68,041.94 of interest. The second mode works backward from a date: finishing 15 years from now takes 587.71 more each month.
The rate is held fixed and each extra amount is applied to principal on its payment date. Escrow for property tax and insurance is left out because it doesn't reduce the balance.
How much do extra mortgage payments save?
Extra payments go straight to principal, so less interest accrues afterward. With 25 years left on a fixed-rate 300,000 at 6.5%, an extra 200 a month ends the loan after 243 payments instead of 300 and saves 68,041.94 of interest.
How the savings are worked out
Each month's interest is the balance × the annual rate ÷ 12. The payment covers that interest first, and the rest, plus any extra, reduces the balance:
Month 1 interest: 300,000 × 6.5% ÷ 12 = 1,625.00.
The regular payment repays 2,025.62 − 1,625.00 = 400.62 of principal; with 200 extra, 600.62.
The balance falls to 299,399.38, so month 2 interest is 1,621.75 instead of 1,622.83.
Repeat until the balance reaches zero, once with the extra and once without. The current plan carries 307,686.45 of interest; the faster plan carries 68,041.94 less.
The current payment itself comes from the standard formula M = B × r × (1 + r)ⁿ ÷ ((1 + r)ⁿ − 1), with r = 6.5% ÷ 12 and n = 300 months left.
Paying extra monthly vs once a year
The same 300,000 balance at 6.5% with 25 years left, three ways:
Extra-payment scenario
Payments until payoff
Interest saved
Monthly 100
268
38719.02
Default
243
68041.94
Yearly 1200
269
36951.22
"Default" is 200 extra every month. "Yearly 1200" adds 1,200 to every 12th payment, starting with payment 12.
Both 100 a month and 1,200 a year put the same amount in each year, but the monthly plan saves 1,767.80 more because each dollar arrives sooner.
A single 10,000 paid with the next payment saves about 37,310 of interest and ends the loan 23 months early.
Do biweekly payments pay off a mortgage faster?
Yes. Twenty-six half-payments a year add up to 13 monthly payments instead of 12.
To model them, enter one monthly payment as a yearly extra: on this loan, an extra 2,025.62 once a year ends it 48 months early and saves about 57,030 of interest.
Extra needed to pay off by a target date
Work backward: find the payment that clears the balance in the months you have, then subtract the current payment. Paying off by 1 October 2041, with the next payment on 1 November 2026, leaves 180 payments.
The payment that clears 300,000 at 6.5% in 180 months is 2,613.33, so the extra is 587.71 a month, rounded up to the cent. That ends the loan ten years early and saves 137,289.63 of interest.
If you know the payment but not the years left
The number of payments left is n = −ln(1 − B × r ÷ M) ÷ ln(1 + r), the same figure Excel's NPER returns. For 230,000 at 6% paying 1,500 a month, B × r ÷ M = 0.766667, and n = 291.78, so 292 payments remain, the last one smaller.
Adding 500 a month to that loan cuts it to 172 payments and saves 94,554.73 of interest.
Before you send extra money
Check for a prepayment penalty. The CFPB explains that these usually apply when you pay off all or a large part of the loan within a set number of years, often three or five.
Tell the servicer to apply it to principal. The savings exist only if the extra reduces the balance instead of sitting as an early payment.
Compare the rate. Each extra dollar saves interest at the mortgage rate, 6.5% here. Paying down debt at a higher rate saves more per dollar.
Leave escrow out. Property tax and insurance in the monthly bill do not reduce the balance.
These figures assume the rate stays fixed for the rest of the loan.
What to enter
The balance still owed, from your latest statement.
The payment for principal and interest only, which must exceed the month's interest: 1,625.00 on 300,000 at 6.5%.
A yearly extra lands on every 12th payment from the payment number you pick, and a one-time extra on its chosen payment.
372,217.43 left at 6% over 25 years, 500 extra a month
Calculate
Extra payments
Current loan balance
372,217.43
Interest rate
6%
I know my
Remaining term
Years left
25 years
Plus months
0 months
Extra every month
500
Extra once a year
0
One-time extra payment
0
Next payment date
in 1 month
Current monthly payment
2,398.20
Payments left with extra
207
Time saved
93 months
Interest saved
122,306.00
Checked against: Calculator.net mortgage payoff calculator, published example: paid off in 17 years 3 months, 7 years 9 months earlier, saving $122,306
230,000 at 6% paying 1,500, plus 500 a month
Calculate
Extra payments
Current loan balance
230,000
Interest rate
6%
I know my
Monthly payment
Monthly payment (principal and interest)
1500
Extra every month
500
Extra once a year
0
One-time extra payment
0
Next payment date
in 1 month
Payments left now
292
Payments left with extra
172
Time saved
120 months
Interest left to pay now
207,677.36
Interest left with extra payments
113,122.63
Interest saved
94,554.73
Checked against: Calculator.net mortgage payoff calculator, published example (remaining term unknown): 14 years 4 months, 10 years earlier; interest 207,677.36 vs 113,122.63
Monthly, yearly and one-time extras together
Calculate
Extra payments
Current loan balance
300,000
Interest rate
6.5%
I know my
Remaining term
Years left
25 years
Plus months
0 months
Extra every month
200
Extra once a year
2000
First yearly extra with payment no.
12
One-time extra payment
10,000
One-time extra with payment no.
1
Next payment date
in 1 month
Payments left with extra
200
Time saved
100 months
Interest saved
122,421.65
Checked against: Month-by-month loop: 200 every month, 2,000 with payments 12, 24, …, 10,000 with payment 1
Extra needed to finish by October 2041
Calculate
Payoff by a date
Current loan balance
300,000
Interest rate
6.5%
I know my
Remaining term
Years left
25 years
Plus months
0 months
Pay off by
2041-10-01
Next payment date
2026-11-01
Extra needed each month
587.71
Payments left with extra
180
New payoff date
2041-10-01
Interest saved
137,289.63
Checked against: 180 monthly payments from 2026-11-01; PMT(6.5%/12, 180, 300,000) = 2,613.3221 minus 2,025.6215, rounded up to the cent
Questions
How much faster will extra payments pay off my mortgage?
It depends on the rate and the balance, but even small amounts cut years. On 300,000 at 6.5% with 25 years left, the payment is 2,025.62. An extra 100 a month ends the loan 32 months early and saves 38,719.02 of interest; an extra 200 a month ends it 57 months early, 4 years 9 months, and saves 68,041.94.
How much extra do I need to pay to own my home in 15 years?
Enough to make the payment equal the amount that repays the balance in 180 months. For 300,000 at 6.5%, that payment is 2,613.33, so 587.71 more than the 25-year payment of 2,025.62. It ends the loan 10 years early and saves 137,289.63 of interest. Choose "Payoff by a date" to run your own target.
Is a yearly lump sum as good as paying extra every month?
Almost, but money paid earlier saves more. On the default 300,000 loan at 6.5%, 100 extra every month saves 38,719.02 and 32 months, while 1,200 paid once a year, starting with the 12th payment, saves 36,951.22 and 31 months. A single 10,000 payment now saves 37,310.11 and ends the loan 23 months early.
Do biweekly payments pay off a mortgage faster?
Yes, because 26 half-payments a year equal 13 monthly payments, one more than the usual 12. To model it, enter your monthly payment as the yearly extra. On the default loan, an extra 2,025.62 once a year ends the loan 48 months early and saves 57,029.48 of interest. Adding one-twelfth of the payment, 168.80, to every monthly payment instead ends it 50 months early and saves 59,673.28.
Is there a penalty for paying off a mortgage early?
Usually not for extra principal paid in small amounts. The Consumer Financial Protection Bureau says prepayment penalties normally apply when you pay off the whole balance, or a large part of it, within a set number of years, usually three or five. Check your loan documents or ask your servicer before sending a large lump sum.
For planning only. Lenders, tax authorities and markets apply their own rounding, fees and rules; confirm figures with them before you commit.
Checked against references
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