The biweekly trick — without paying a fee
Mortgage servicers love to charge for 'biweekly conversion programs' because most homeowners don't realize the math. The honest version: take your monthly payment, divide by 12, add that to your monthly payment, mark it as 'apply to principal.' Same result. Free. Reversible whenever you want.
- • $3,000 monthly payment ÷ 12 = $250 extra/month to principal.
- • Same effect as 26 biweekly $1,500 payments.
- • No servicer enrollment, no $200–500 fee, no auto-debit lock-in.
Why it works so well early in the mortgage
On a brand-new $400K mortgage at 7%, your first payment is $2,661 — but only $328 of that goes to principal. The other $2,333 is interest. An extra $221/month ($2,661/12) of principal early in the loan eliminates the equivalent interest at compounding, which is why the savings compound to $60K–80K over the life of a 30-year mortgage.
When NOT to do biweekly
Skip biweekly if: (1) your mortgage rate is below 4% — investing the extra at 7–10% expected returns beats paying down a 3% loan; (2) you're not maxing 401(k) match — leaving free money on the table is always worse; (3) you have higher-rate debt (credit cards, personal loans); (4) you don't have 3-6 months emergency fund; (5) you'd rather have the liquidity for life events.
Biweekly vs. one annual extra payment vs. recast
All three reduce lifetime interest. Biweekly + 1/12 monthly: smooth cash flow, daily compounding benefit. One annual lump (e.g., from tax refund or bonus): same total savings but slightly less impact because money sits idle 11 months. Mortgage recast: after a $5K+ lump sum, servicer re-amortizes the loan to the lower balance, dropping the monthly payment without changing the rate — useful when income drops.
FAQ
Does biweekly really save money?
Yes — by paying the equivalent of one extra monthly payment per year, you cut a typical 30-year mortgage down to 23–26 years and save 15–25% of total lifetime interest. The math is straightforward and uncontested.
Should I pay for a biweekly conversion program?
No. Servicer programs that charge $200–500 (or $9/month) deliver no benefit you can't get for free by adding 1/12 of your monthly payment each month and marking it 'apply to principal.'
Will my mortgage company accept biweekly payments?
Some do, some don't. Servicers that don't accept biweekly will hold your half-payment until the full amount arrives, defeating the purpose. The DIY approach (1/12 extra monthly to principal) works with every servicer.
Does biweekly hurt my credit score?
No. The credit bureau sees only the monthly account status — current, late, default. Paying more frequently or in larger amounts has no bearing on score.
Can I undo biweekly if my finances change?
Yes if you DIY (just stop sending extra). If you enrolled in a paid servicer program, you may need to cancel by phone and may have early-termination fees. Another reason to DIY.
What if my rate is under 3%?
Don't accelerate. A 2.5–3% mortgage is the cheapest leverage available in modern history — keep it for 30 years and invest the difference. Index funds returning 8–10% expected annually outperform 3% guaranteed savings.
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Written by Sam Doshi and the RevenueLab editorial team. We don't sell the data feeds this tool is built on.
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Last reviewed
June 2026. We re-check every figure on the platform on a rolling quarterly cycle.
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