Reviewed May 22, 2026

Biweekly Mortgage Calculator

See how 26 half-payments per year changes your mortgage payoff, then compare it with the no-fee strategy of adding one-twelfth of your monthly payment as extra principal each month.

Biweekly Mortgage Payment Calculator

Model 26 half-payments per year, compare the no-fee monthly equivalent, and see whether a paid biweekly plan is worth it.

$
%
years
$
$
Interest saved
$110,411
before optional program fees
Payoff faster by
6 years
new payoff: 24 years
Biweekly payment
$1,135.05
26 half-payments per year
Net savings
$110,411
$0 estimated fees
Regular monthly P&I payment$2,270.09
No-fee DIY extra principal per month$189.17
Extra principal added per year$2,270.09
Standard total interest$467,234
Biweekly-equivalent total interest$356,822
Original payoff timeline30 years
Biweekly-equivalent payoff timeline24 years

Best no-fee setup

Add $189.17 as extra principal to each monthly payment. That is usually equivalent to one extra full payment per year without paying a third-party plan.

Servicer instruction

Tell the servicer to apply extra money to principal, not to future scheduled payments. Keep screenshots or confirmation numbers after changing payment instructions.

Fee check

If a paid plan charges more than your modeled savings, skip it and use the DIY extra-principal approach. The calculator subtracts setup and monthly fees from projected savings.

What the Calculator Assumes

The calculator treats a biweekly plan as the reliable monthly-amortization equivalent of one extra principal-and-interest payment per year. In practical terms, 26 half-payments equal 13 full payments, so the no-fee comparison is adding one-twelfth of your regular P&I payment as extra principal each month.

Some servicers post payments differently, and some third-party programs may charge fees. For that reason, the calculator separates gross interest savings from fee-adjusted net savings and tells you the monthly DIY extra-principal amount to request from your servicer.

Biweekly Payments vs. One Extra Mortgage Payment Per Year

The appeal of biweekly payments is behavioral: paying half your mortgage every two weeks can line up with a biweekly paycheck and quietly creates one extra full payment each year. The math is not magic. The extra annual principal is what reduces future interest and shortens the loan.

If your regular P&I payment is $2,270, a true biweekly schedule pays $1,135 every two weeks. The free DIY version is simpler: add about $189.17 to each monthly payment as extra principal. Both approaches create about one extra full payment per year before fees.

Use biweekly when

Your servicer supports it cleanly, there are no fees, and the schedule helps you stay consistent.

Use DIY extra principal when

A third-party plan charges fees, holds funds, or makes it unclear when extra money reaches principal.

Pause before prepaying when

You lack emergency savings, have high-interest debt, or your loan documents include unusual prepayment terms.

Source Review

Frequently Asked Questions

How many payments do I make with a biweekly mortgage?

You make 26 half-payments per year. That equals 13 full monthly payments, which is one more full payment than a standard monthly schedule.

Can I do biweekly mortgage payments myself?

Usually yes. The simplest version is adding one-twelfth of your regular monthly P&I payment as extra principal each month. Ask your servicer how to label that payment so it goes to principal.

Are paid biweekly mortgage programs worth it?

Only if the fee is small relative to the interest saved and the program applies payments correctly. Many borrowers can get similar math for free by making monthly extra-principal payments.

Does this calculator include taxes and insurance?

No. It focuses on principal and interest payoff math. Property taxes, homeowners insurance, HOA dues, and escrow changes do not affect the principal payoff schedule unless your total cash flow changes.

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