26 half-payments a year is one extra payment — here is what it buys
Biweekly on this loan is $250/mo of extra principal. The toggle opposite is set to it — change the amount to compare against any other plan.
Principal & Interest payment only (P&I)
$2,998/mo
26 half-payments a year is one extra payment. An early dollar saves more than a late one — see the prepay curve.
Want the lump sum to lower your payment instead? Try a recast.
Compare extra monthly payments
Interest saved ($)
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You'll Save
$122,846
with $250/month extra
Years saved
5.4
New payoff
24.6 yrs
Return*
167.1%*
Standard vs Extra Payments
Balance Over Time
Remaining balance ($)
Most servicers accept extra principal for free — the official biweekly program usually charges for it. Today’s rates →
Altgage Inc. NMLS #2447252 | 100 Cambridge St, Floor 14, Boston, MA 02114Biweekly mortgage payments aren't magic — they work because you make 26 half-payments per year (52 weeks ÷ 2), which equals 13 full payments instead of 12. That one extra payment per year, applied to principal, shaves 5–7 years off a 30-year loan and saves tens of thousands in interest. You can do it for free, but most servicers charge for the official program.
One extra full payment per year goes 100% to principal — bypassing the front-loaded interest schedule on amortization. On a typical 30-year, this knocks ~6 years off and saves ~$60K–$80K depending on balance and rate. Bigger gains happen earlier in the loan (when interest dominates) than later.
Divide your monthly payment by 12 and add that amount to each monthly payment, applied to principal. Equivalent math, no servicer fee, no separate program. Your servicer accepts extra principal payments any time — just make sure the extra goes to principal, not the next month's interest. Set up an automatic recurring transfer.
Most servicers offer this for $200–$400 setup plus $3–$10 per debit. They take the payment every 2 weeks and hold the extras until they make the full extra payment annually. Functionally identical to the DIY version but with fees. Worth it only if forced automation matters more to you than the fees.
Your loan rate is low and you'd earn more investing the extra payment. You're not maxing your retirement contributions yet (those usually win on after-tax return). You have higher-interest debt (credit cards, personal loans) that should get paid first. Or you're planning to refi soon — wait until after the refi to start.
Yes, but not because of the payment frequency. Twenty-six half-payments a year equals thirteen full payments instead of twelve, and that one extra payment applied to principal is where all the savings come from. Adding one-twelfth of your payment monthly produces the same result.
Usually not. Servicers commonly charge a setup fee plus a per-debit fee for a program you can replicate for free by adding one-twelfth of your payment to each monthly payment and marking it for principal. You’re paying for enforced automation, not for a different outcome.
Roughly four to six years off the term and tens of thousands in interest, depending on your balance and rate. Starting early matters more than the exact amount — the same schedule begun in year one and year ten produce very different totals.