See how bi-weekly payments cut 4–6 years off your mortgage with one extra payment per year.
Switching from monthly to bi-weekly payments adds one extra full payment per year — applied entirely to principal. This calculator shows exactly how many years come off and how much interest you save.
Direct answers to the most common questions, in plain language. Skim if you're in a hurry; dig deeper below.
Typically 4–6 years and 20–30% of interest on a 30-year loan.
On a $300k, 30-year mortgage at 7%, switching to bi-weekly payments cuts the loan by about 5 years 8 months and saves roughly $80,000 in interest. The savings come from making one extra full payment per year.
You pay half your monthly payment every two weeks.
There are 52 weeks in a year, so bi-weekly results in 26 half-payments — equivalent to 13 full monthly payments instead of 12. That one extra payment per year goes entirely to principal.
Most do, but some charge enrollment fees.
Many lenders offer official bi-weekly programs, sometimes with $5–10 monthly fees. You can also DIY it by adding 1/12th of your payment monthly — same math, no fees, same result.
Effectively identical — pick whichever you'll actually do.
Paying 1/12 of your payment extra each month gives the same annual extra payment as bi-weekly, often with more flexibility and no enrollment fees. The math is essentially the same.
The mechanics in short answers — no jargon, no upsell.
You pay half your monthly payment every 14 days. Across 52 weeks, that's 26 half-payments — the equivalent of 13 full monthly payments instead of the usual 12.
Your 13th payment doesn't get split between interest and principal — the entire amount reduces your loan balance, and every future interest calculation uses the new lower number.
In the first 10 years of a 30-year mortgage, most of your monthly payment is interest. The extra payment in those years saves multiples of what it saves later.
You can replicate the exact savings by adding 1/12 of your monthly payment to your check each month — no enrollment fee, no third-party service.
Designed so anyone can model their situation in under a minute, with or without a finance background.
One extra payment per year compounds dramatically — see exactly how many months you save.
20–30% interest reduction is typical on a 30-year loan, depending on rate.
If you're paid every two weeks, bi-weekly aligns your cash flow with your bills.
Accelerate payoff without origination fees, appraisals, or new closing costs.
Bi-weekly is a risk-free return equal to your rate — better than most fixed-income alternatives.
Your new payoff date pops out instantly — visualize the years saved.
Everything you might ask before, during, or after using this tool.
Most do, but enrollment varies. Some run official bi-weekly programs (often with a small monthly fee). Others won't accept partial payments and will hold them until a full payment is reached. If yours doesn't, the DIY version — adding 1/12 of your payment to every monthly payment — gives the same result.
Lender programs sometimes charge $5–10/month or a $300 setup fee. Third-party bi-weekly services charge similar fees. The DIY approach (extra 1/12 each month) is free and mathematically equivalent.
No. It actually helps — your balance drops faster, which improves your debt-to-income ratio over time. The accelerated payoff doesn't change how the payment is reported.
If you're doing the DIY version (extra 1/12 monthly), yes — just stop the extra. If you're enrolled in a lender program, you typically need to cancel formally. The DIY approach is more flexible.
Marginally. You pay slightly less total interest over the life of the loan, so your itemized mortgage-interest deduction is smaller in later years. The interest savings vastly outweigh the lost deduction.
Refinancing to a 15-year mortgage saves the most absolute interest, but the monthly payment jumps significantly. Bi-weekly on a 30-year keeps your minimum payment manageable while still saving 4–6 years. Many borrowers prefer the flexibility of bi-weekly.
No — your minimum required payment stays the same. The "savings" show up as a shorter loan and less total interest, not a lower bill each month.
If you have higher-interest debt (credit cards, personal loans), pay those first — they cost more than your mortgage. If you don't have an emergency fund, build that first. Bi-weekly is great only after the basics are covered.
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Bi-weekly works because there are 52 weeks in a year, not 48. Half-payments every two weeks = 26 half-payments = 13 full monthly payments. That one extra payment per year is the entire source of the savings.
The extra payment isn't split between interest and principal — it's applied 100% to principal. Every future interest calculation then runs against a smaller balance, compounding the effect.
Lender programs: convenient autopay, sometimes a small fee, mostly identical math.
DIY approach: add 1/12 of your monthly payment to every monthly payment. Zero fees, full flexibility, same outcome.
Third-party bi-weekly services: usually charge fees for what you can do yourself. Avoid.
Refinancing to a 15-year saves more total interest, but spikes your monthly payment by 25–50% — a big commitment.
Bi-weekly on a 30-year saves less than a 15-year but keeps your minimum payment low. If money gets tight, you can pause; with a 15-year, you can't.
For most borrowers, bi-weekly is the right balance of acceleration and flexibility.
You carry credit-card or personal-loan debt — pay that off first; the rates are higher.
You don't have 3–6 months of expenses in an emergency fund — fund that first.
You're not maxing employer 401(k) match — that's free money worth more than the mortgage acceleration.
You're planning to sell within 5 years — the savings won't fully materialize.
Two short notes worth reading before you trust any number on this page.
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Results are not financial, legal, or tax advice. Please consult a qualified professional before any decision about your loan, investments, or personal finances. Actual loan terms and charges depend on your bank and individual circumstances.
