US MortgageCalculator
Back to main calculator

Biweekly Mortgage Payment Calculator

A biweekly mortgage plan means paying half your monthly payment every two weeks instead of the whole thing once a month. Because there are 26 fortnights in a year and only 12 months, that works out to 13 monthly payments annually rather than 12 — and that thirteenth payment, applied entirely to principal, takes years off a 30-year loan. This calculator shows exactly how many, and explains why you do not need to sign up for anything to get it.

How to use this calculator

  • - Enter the loan amount, not the purchase price.
  • - Twenty-six half-payments a year equals thirteen monthly payments — that extra one is the whole effect.
  • - The equivalent monthly overpayment is shown, because it costs nothing to arrange.

Your loan

Principal and interest only.

Loan

The amount borrowed, not the purchase price.

Interest saved

$93,073

Paid off 5 yr 10 mo sooner

Monthly payment$2,022.62
Biweekly paymentHalf the monthly payment, every two weeks$1,011.31
Paid per year26 half-payments, not 24$26,294
Extra principal per year$2,023
Payoff, monthly30 yr
Payoff, biweekly24 yr 2 mo

You can do this without signing up for anything

Twenty-six half-payments a year is thirteen monthly payments, so the entire effect is one extra payment of principal annually. Paying $168.55 extra each month reaches the same place, with no enrolment and no servicer fee.

What this assumes

  • 26 biweekly half-payments equal 13 monthly payments a year. The thirteenth goes entirely to principal, which is the whole effect.
  • Modelled as the equivalent monthly overpayment. A true 14-day accrual differs by a small amount depending on how the servicer applies payments.
  • Some servicers charge to set up biweekly billing, or hold each half-payment until the full amount arrives, which cancels the benefit. Paying one-twelfth extra each month achieves the same thing for free.

The arithmetic, stated plainly

There is nothing clever happening. Twenty-six half-payments equal thirteen full payments. The extra one lands on principal, the balance falls faster than the schedule assumes, and every subsequent month accrues slightly less interest. Compounded across three decades, that single extra payment a year typically retires a 30-year loan in about 26 and saves tens of thousands in interest.

The effect is real, and it is also entirely reproducible by paying one twelfth extra with each ordinary monthly payment. The calculator above reports that figure alongside the biweekly one, because they reach the same destination and one of them requires no arrangement with anybody.

Where biweekly plans go wrong

  • Enrolment fees: Some servicers and third-party companies charge a setup fee plus a per-transaction charge to administer a biweekly plan. You are paying for the privilege of sending your own money to your own loan. A standing order for the equivalent monthly amount costs nothing.
  • Payments held in suspense: Many servicers do not apply a half-payment when it arrives. They hold it until the second half turns up, then apply a full monthly payment. If that is how yours works, paying biweekly changes nothing at all except the timing of the money leaving your account — the benefit only appears when the thirteenth payment is finally applied.
  • Extra not applied to principal: An overpayment can be applied to principal, held as a prepayment of next month, or parked in escrow. Only the first reduces the balance. Whichever route you take, tell the servicer in writing that additional funds are to be applied to principal, and check the next statement.

When paying it down is the wrong move

Retiring a mortgage early is a guaranteed return equal to your interest rate, tax-free in the sense that you are avoiding a cost rather than earning income. Against a 7% mortgage that is a strong return. Against a 3% mortgage taken out in 2021, it is a poor one — the same money in a savings account has recently paid more, with the additional advantage of remaining accessible.

The ordering that holds for most households: clear high-interest consumer debt first, then capture any employer retirement match in full, then build a cash reserve of several months' expenses, and only then consider extra principal. A paid-down mortgage is not a liquid asset. Money paid into it cannot be retrieved without selling the house or borrowing against it, which is precisely what you cannot do easily in the circumstances where you would need it.

Frequently asked questions

How much can biweekly payments save?

On a typical 30-year loan the effect is roughly four to five years off the term and a five-figure reduction in total interest. The exact numbers depend on the rate and balance — the calculator above computes both for your loan. Higher rates produce larger savings, because the interest you are avoiding is larger.

Is a biweekly mortgage worth it?

The extra payment is worth it whenever your mortgage rate exceeds what the money would safely earn elsewhere, and once you have cleared higher-interest debt and built a cash reserve. The biweekly wrapper specifically is worth nothing extra — pay one twelfth more each month and you get the identical result without enrolling in anything.

Do all lenders accept biweekly payments?

Most accept the money, but a good number hold half-payments in a suspense account rather than applying them immediately, which delays the benefit. Ask your servicer two questions before changing anything: whether half-payments are applied on receipt, and whether extra funds go to principal by default. If either answer is unsatisfactory, pay monthly with an explicit principal-only addition.

Should I pay off my mortgage early or invest?

Compare your mortgage rate against a realistic after-tax return on the alternative, and weigh liquidity. Paying down a 7% mortgage is a solid guaranteed return that is hard to beat safely. Paying down a 3% mortgage while holding no emergency fund is usually the wrong order of operations, because the money becomes inaccessible exactly when you might need it.

Reference sources

Related calculators

Extra payments calculator15 vs 30 year calculatorPMI calculatorClosing cost calculatorAPR calculatorProperty tax calculator

For developers

This calculation is also available as a REST API and through an MCP server, both running the same engine as this page — so the figures match by construction rather than by convention. No key required.