The biweekly trick: split your monthly payment in half, pay that amount every two weeks. Because there are 52 weeks in a year, you make 26 half-payments = 13 full payments, not 12. That one extra payment per year, applied to principal, shortens a 30-year loan to roughly 25 years and saves $50K-$100K in interest on a typical loan.
Worked example: $350,000 loan at 7% for 30 years. Monthly P&I = $2,328. Biweekly = $1,164 every 2 weeks. Over the life of the loan you pay 5 years 10 months less and save $88,500 in interest.
Is your servicer actually applying biweekly correctly?
Many mortgage servicers do NOT apply each half-payment immediately. They hold your payment in suspense, and when the second half arrives they apply the combined payment on the due date. Result: you make 26 payments but they credit as 12 monthly + 1 extra annual. The savings still happen — just not via the extra-interest-accrued mechanism some calculators assume. Call your servicer and ask: "When I pay half on the 1st and half on the 15th, do you credit immediately or hold until 1st of next month?"
The <Link href=/biweekly-vs-extra>biweekly vs extra 1/12 monthly</Link> debate
Instead of paying biweekly, you can just add 1/12 of your monthly payment to each monthly check (a $2,328 payment becomes $2,522). Same savings, and you avoid biweekly enrollment fees (some servicers charge $4-$10/payment, which is criminal). For most homeowners, the DIY extra-principal route is better. See the biweekly vs extra calculator for side-by-side.
When biweekly wins
- You are paid biweekly and it matches your cash flow
- Your servicer applies biweekly correctly with no fee
- You need the forced discipline of an automatic draft