10/18/2026
A $500,000 mortgage at 4% costs $359,347 in interest over 30 years. That is the cheap version. At this week's average rate, the same loan costs more than twice that. On a 4% loan the monthly principal and interest payment is $2,387.08. Paid on schedule for 360 months, the total comes to $859,347. The biweekly idea runs on the calendar, not on any special product. Half a payment every two weeks means 26 half payments in a year, because a year has 52 weeks. Twenty-six halves are 13 full payments instead of 12, and that one extra payment a year goes straight at principal. On the 4% loan, one extra payment a year, applied as it arrives, ends the loan in about 25 years and 11 months, roughly four years early, and saves about $55,663 in interest. Freddie Mac's survey put the average 30-year fixed rate at 7.40% on October 15, 2026, and at that rate the same habit on the same $500,000 ends the loan about six and a half years early and saves roughly $190,000, because every dollar of principal removed was costing more. The schedule only works if the money is applied when it arrives. The Consumer Financial Protection Bureau has taken action against biweekly payment companies over exactly this. In one case, from 2015, the setup fee ran up to $995, with $84 to $101 a year in processing fees on top. The same result is available without a program. One extra full payment a year, or one twelfth of a payment added to each monthly payment and marked for principal, does nearly the same work. On the 4% loan that is about $199 a month. Sources: Freddie Mac PMMS, Oct. 15, 2026; standard 30-year amortization; CFPB actions against Paymap and Nationwide Biweekly (2015). Educational information only, not financial, tax, legal, or investment advice. Loan terms differ, so confirm with the servicer before changing how payments are made.
