Bi-Weekly Mortgage Payment Calculator — Interest Saved
Paying half your monthly mortgage every two weeks results in 26 half-payments per year — equivalent to 13 full monthly payments instead of 12. That one extra annual payment chips away at principal faster, cutting years off the loan and saving thousands in interest. Enter your loan details to see the exact comparison.
$
%
years
Half the monthly payment, made every two weeks — 26 payments per year (= 13 full monthly payments)
- 1
Monthly interest rate
r = 6.5 % ÷ 12 ÷ 100 = 0.005417 - 2
Number of monthly payments
n = 30 × 12 = 360 - 3
Growth factor
(1 + r)ⁿ = 6.9918Compound growth factor over the full loan term at the monthly rate. - 4
Monthly payment
300,000 × 0.005417 × 6.9918 ÷ (6.9918 − 1) = 1,896.2 - 5
Bi-weekly payment
1,896.2 ÷ 2 = 948.10Paying half the monthly amount 26 times/year equals 13 full monthly payments.
How does this calculator work?
Bi-weekly mortgage payment = M/2, paid 26 times per year. That equals 13 monthly payments/year instead of 12. The extra annual payment reduces principal faster, cutting years off the term and saving significant interest. Use M = P·r_m(1+r_m)^n/(…) for the monthly payment, halve it, and simulate amortisation at the exact bi-weekly compound rate.
Formula
How this is calculated
A standard mortgage makes 12 monthly payments per year. A bi-weekly plan makes 26 payments of exactly M/2. Because 26/2 = 13, you effectively make one extra full monthly payment every year — without any single payment being noticeably larger.
The monthly payment M uses the standard amortisation formula with the monthly interest rate r_m = annual_rate/12. For the bi-weekly schedule, the calculator uses the exact compound bi-weekly rate r_bw = (1 + annual_rate)^(1/26) − 1 (not a simple annual/26 approximation). The payoff period n_bw follows directly from the annuity formula, and total interest = total paid − principal.
The interest saving grows with loan size, rate, and term. Note that some lenders charge a fee to set up a formal bi-weekly programme; this calculator assumes no such fee. The same acceleration is achievable by making one additional principal payment each year, or by adding 1/12 of M to each monthly payment.
Frequently asked questions
Many lenders accept them but some require enrolment in a specific scheme, sometimes with a fee. Check your loan agreement. An equivalent strategy that avoids any programme fee is to make one extra principal-only payment per year, or to add one-twelfth of your monthly payment to each monthly payment.
Mortgage interest accrues on the outstanding balance. Paying two weeks earlier than the monthly due date reduces the balance sooner, so less interest accrues in that period. Over time, the compounding effect of the extra annual payment dramatically reduces the principal and total interest paid.
Yes. This calculator assumes the rate is fixed for the entire term. For adjustable-rate or variable-rate mortgages the payment and savings will change with each rate reset.
TG we-Calculate Editorial Team. (2026). Bi-Weekly Mortgage Payment Calculator — Interest Saved [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/bi-weekly-mortgage-payment-calculator
TG we-Calculate Editorial Team. "Bi-Weekly Mortgage Payment Calculator — Interest Saved." TG we-Calculate. 2026. https://we-calculate.com/calculator/bi-weekly-mortgage-payment-calculator.
TG we-Calculate Editorial Team, "Bi-Weekly Mortgage Payment Calculator — Interest Saved," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/bi-weekly-mortgage-payment-calculator
@misc{wecalculate_bi_weekly_mortgage_payment_calculator, title = {Bi-Weekly Mortgage Payment Calculator — Interest Saved}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/bi-weekly-mortgage-payment-calculator}}, year = {2026}, note = {TG we-Calculate} }
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