Biweekly Mortgage Calculator
See how much time and interest a biweekly payment schedule saves — and how a free do-it-yourself alternative usually gets you nearly the same result without paying a third-party service to do it.
Want the standard amortization breakdown instead? See our Mortgage Amortization Calculator, or all our calculators.
Glossary
There are 52 weeks in a year, so paying half your normal monthly payment every 2 weeks works out to 26 half-payments — the equivalent of 13 full monthly payments a year instead of 12. That extra payment goes entirely toward principal, which shortens your loan and cuts total interest.
Rarely, and only if it’s genuinely free. Ask your loan servicer directly whether they offer a no-fee biweekly draft option first. If a third-party company is charging a setup fee and per-transaction fees, confirm exactly how and when your extra payments actually reduce your principal — some programs simply hold your payments and forward them monthly, which provides no benefit at all despite the fee.
Instead of splitting your payment in two and paying every 2 weeks, you simply add 1/12 of a normal payment as extra principal to your regular monthly payment. It adds the same extra ~8.3% a year toward principal, so the results land close to true biweekly — true biweekly is usually slightly better since the extra principal is applied more frequently throughout the year, but the DIY version costs nothing to set up.
For the DIY approach, just make sure any extra amount you send is applied to principal, not held as a credit toward next month’s payment — most servicers let you specify this online or by note with your payment; some don’t support it automatically, so confirm before assuming it’s working as intended.