Biweekly Mortgage Calculator
Enter your loan amount, interest rate, and term to compare a standard monthly payment against an accelerated biweekly schedule, and see the interest and time you could save.
Compare payment schedules
Original loan amount, from $1 through $100,000,000.
Annual interest rate, from 0% through 25%.
Whole years for the loan, from 1 through 50.
Switching to biweekly payments could save $74,436.02 in interest and pay off 66 months sooner.
- Monthly payment
- $1,798.65
- Biweekly payment
- $899.33
- Months saved
- 66
| Schedule | Payment | Time to pay off | Total interest |
|---|---|---|---|
| Monthly | $1,798.65 | 30 years | $347,514.57 |
| Biweekly | $899.33 | 24 years, 6 months | $273,078.55 |
Biweekly payments clear the loan 66 months sooner because the schedule adds the equivalent of one extra monthly payment each year.
How the biweekly schedule is modeled
The monthly plan uses the level payment that amortizes the loan over its full term at the monthly periodic rate. The biweekly plan pays half that monthly amount every two weeks. Because there are 26 biweekly periods in a year, that adds up to 13 monthly payments’ worth each year instead of 12 — the equivalent of one extra monthly payment annually — which pays the principal down faster and reduces total interest.
Monthly payment = L × r / (1 − (1 + r)−n)Biweekly payment = Monthly payment ÷ 2, charged every 2 weeks- L
- Loan amount
- r
- Monthly periodic rate (annual rate ÷ 12)
- n
- Number of monthly payments (term × 12)
$300,000 at 6% over 30 years
A $300,000 loan at 6% over 30 years has a monthly payment of $1,798.65. Split into a biweekly payment of $899.33 charged every two weeks, the loan is paid off in about 294 months — roughly 66 months sooner — saving $74,436.02 in interest.
This is an educational calculation based only on the values you provide. It does not look up your live loan terms, and it is not financial advice.
What this calculator assumes
- The interest rate stays fixed for the whole payoff period.
- The biweekly payment is exactly half the monthly payment, charged every two weeks (26 times a year).
- Your lender applies each biweekly payment when received rather than holding it until a monthly due date.
- Taxes, insurance, HOA dues, and PMI are excluded — this models principal and interest only.
- Money values are rounded to the nearest cent for display.
Biweekly mortgage FAQ
Why does paying biweekly save money?
Twenty-six biweekly half-payments equal 13 full monthly payments a year rather than 12. That extra payment goes straight to principal, so the balance falls faster and accrues less interest over the life of the loan.
Does my lender have to accept biweekly payments?
Not always. Some servicers hold biweekly payments and only apply them monthly, or charge a fee to enroll. Confirm your lender applies payments when received; otherwise you can replicate the benefit by adding one-twelfth of a payment to each monthly bill.
Sources and review notes
Methodology last checked Jul 14, 2026. Formula implementation is covered by deterministic unit tests. No financial professional review is claimed yet.