Bi-Weekly Mortgage Payment Calculator
Compare bi-weekly vs monthly mortgage payments and see the interest and time you save by making 26 half-payments a year.
How bi-weekly mortgage payments save you money
The entire benefit of a bi-weekly mortgage comes from a calendar quirk. Instead of one full payment each month — 12 a year — you pay half your monthly amount every two weeks. Because there are 52 weeks in a year, that works out to 26 half-payments, which equals 13 full monthly payments rather than 12. That single extra payment each year is applied to principal.
That extra principal lowers the balance interest is charged on, so the loan amortizes faster and total interest drops. Note that bi-weekly is not the same as twice-a-month: paying twice monthly is still only 24 payments a year and produces no extra payment. On a typical 30-year mortgage, the bi-weekly approach commonly shortens the term by roughly four to six years and saves thousands in interest, with the exact figures depending on your rate and balance. This calculator models it as adding one-twelfth of a monthly payment to principal each month — algebraically equivalent and free of calendar drift — and shows the interest and time you would save.
A practical tip: you usually do not need to enroll in a paid bi-weekly program to get this benefit. You can replicate it for free by dividing your monthly payment by 12 and adding that amount to each monthly payment yourself. Whichever route you choose, confirm with your servicer that the extra is applied to principal and that your loan has no prepayment penalty. Bi-weekly payments tend to help most when your interest rate is higher; at a very low rate, other uses of the money may serve you better.