Biweekly Mortgage Calculator

Twenty-six half-payments a year quietly equal thirteen full payments — one extra payment annually that your budget barely notices. See how much interest that simple shift saves you.

1 · Afford2 · Payment3 · Schedule4 · Pay off early5 · Closing costs6 · PMI7 · Refinance8 · Rates guide
$
$
%

Results update as you type. Nothing is uploaded or stored.

Why biweekly works (it is arithmetic, not magic)

There are 26 two-week periods in a year, so 26 half-payments = 13 monthly payments. That extra payment goes entirely to principal. On a $320,000 loan at 6.5%, biweekly payments retire the loan in about 23 years 10 months instead of 30 years and cut total interest from $408,143 to roughly $290,360 — a saving of about $117,800.

Three ways to do it — only two are free

  1. Servicer programs — convenient, but some charge setup fees of $300–$400 plus monthly fees, and hold your money until a full payment accumulates. The fees can erase much of the benefit.
  2. DIY biweekly — if your servicer applies extra principal immediately, pay half every two weeks yourself at no cost.
  3. The monthly shortcut — divide your payment by 12 and add that to every monthly payment. Same 13th payment, simpler bookkeeping, zero fees. The payoff calculator models this exactly.

Whichever route you choose, confirm in your servicer portal that extra funds post to principal. Aligning payments with a biweekly paycheck also smooths cash flow for many households. For the full picture of your schedule either way, the amortization calculator shows every payment.

Your next steps

Shortcut version

Payoff calculator

The monthly 1/12 trick, lump sums and payoff dates.

Full picture

Amortization schedule

Every payment, principal vs interest, year by year.

Learn

Pay off early: full guide

All the acceleration strategies ranked by impact.

Related calculators

Mortgage Payment Calculator

Your true monthly payment with taxes, insurance & PMI.

Amortization Calculator

Every payment, principal vs interest, to payoff day.

Mortgage Payoff Calculator

Extra payments, lump sums, years and interest saved.

Home Affordability Calculator

How much house your income can really carry.

Frequently asked questions

How much do biweekly payments really save?
On a $320,000, 30-year loan at 6.5%, about $118,000 in interest and roughly six years of payments. Savings grow with the rate and balance; at 4% the same loan saves closer to $55,000.
Is biweekly the same as paying twice a month?
No — twice a month is 24 half-payments (12 full payments, no benefit). Every two weeks is 26 half-payments (13 full). The two extra half-payments are the entire trick.
Should I pay for a biweekly program?
Almost never. Third-party programs charge setup and monthly fees to do something you can do free by adding 1/12 of a payment to each monthly payment — with the same interest savings.
Does my servicer have to accept biweekly payments?
Servicers must accept extra principal, but some hold partial payments in suspense until a full payment arrives, which kills the benefit. Check your servicer's policy, or use the monthly 1/12 shortcut instead.
Can I combine biweekly with extra payments?
Yes — biweekly gets you the 13th payment; additional principal on top shortens the loan further. Just keep an emergency fund first and clear higher-interest debt before accelerating a mortgage.

Sources & further reading

Official sources for program rules and consumer rights. Zorvex is not affiliated with these agencies; figures here are estimates for education.