Biweekly Mortgage Calculator
Compare standard monthly payments against a biweekly schedule (26 half-payments per year = one extra payment annually). On a typical $400,000 30-year mortgage at 6.46%, biweekly saves about $115,000 in interest and pays the loan off nearly 6 years early.
Last updated: April 2026 · Source: Freddie Mac PMMS April 2, 2026
Monthly vs biweekly side-by-side
| Metric | Monthly | Biweekly | Savings |
|---|---|---|---|
| Payment amount | $2,518/mo | $1,259/2wk | — |
| Annual cost | $30,213 | $32,731 | +$2,518/yr |
| Total interest | $506,393 | $391,577 | -$114,816 |
| Loan term | 30 years | 24.3 years | -5.8 years |
| Total paid | $906,393 | $791,577 | -$114,816 |
Frequently asked questions
How does a biweekly mortgage payment work?
Instead of making 12 full monthly payments per year, you pay half your monthly amount every two weeks. Because there are 52 weeks in a year, you end up making 26 half-payments — equivalent to 13 full monthly payments per year instead of 12. That extra month's payment goes entirely to principal, which dramatically reduces the total interest you pay and shortens the loan term. On a $400,000 mortgage at 6.46%, this saves roughly $115,000 in interest and pays the loan off about 5 years and 9 months earlier.
How much can I actually save with biweekly payments?
For a $400,000 loan at 6.46% over 30 years: monthly payments cost you about $506,000 in total interest. Switching to biweekly cuts that to about $392,000 — a savings of $115,000 — and reduces the loan term from 30 years to about 24 years and 4 months. The savings scale with both loan size and rate. On a $200,000 loan at the same rate, you save about $57,000. On a $600,000 loan at 7%, you save closer to $205,000. The percentage savings stay roughly the same: about 22-25% of total interest, plus 5-6 years of payments.
Do all mortgage lenders accept biweekly payments?
Most lenders do, but the way they handle them varies. The two main approaches: (1) True biweekly setup — your servicer accepts half-payments every 14 days and immediately applies them to the loan. (2) Held-and-applied — your servicer holds your half-payments in a suspense account and applies them as a regular monthly payment when enough has accumulated, which eliminates the savings. Always confirm your lender's approach in writing before signing up. Some lenders charge a setup fee ($200-400) or monthly fee ($5-10) for true biweekly programs, which can erase a chunk of the savings.
Is there a free way to get the same benefit?
Yes — and it is the smart move. Just divide your monthly payment by 12 and add that amount to your regular monthly payment as extra principal. Example: monthly payment is $2,520, divide by 12 = $210. Pay $2,730 each month and instruct your servicer to apply the extra $210 to principal only. This produces nearly identical savings to a true biweekly schedule, costs nothing, and gives you full flexibility to skip the extra payment in tight months. No setup fees, no third-party services.
Are there any downsides to biweekly mortgage payments?
Three to consider: (1) Reduced flexibility — you commit to higher annual payments, which may strain your budget if income drops. (2) Opportunity cost — extra principal payments earn the equivalent of your mortgage rate. If you have a 4% mortgage and could earn 7-8% in a diversified index fund, investing the extra money may produce a better total return. (3) Setup fees from third-party services — companies that offer to "manage" biweekly payments for you typically charge $200-400 setup plus monthly fees that can negate the savings. Always check if your lender offers it free first.
Is biweekly better than just paying extra principal?
Mathematically, biweekly produces the exact same effect as making one extra monthly payment per year. The difference is structural: biweekly forces consistency through automation, while ad-hoc extra payments rely on willpower. For people who would otherwise spend the money, biweekly is better because the savings happen automatically. For disciplined savers who track every dollar, monthly extras are equally effective and more flexible. Either approach is dramatically better than the standard monthly schedule.
Should I do biweekly if I plan to move in 5 years?
Probably not the best use of cash. Biweekly payments build extra equity that you cannot easily access until you sell or refinance. If you plan to move in 5 years, that locked-up equity might be better invested in a high-yield savings account (currently around 4-5% APY) or low-cost index funds, where it remains liquid for the down payment on your next home. Biweekly mortgage payments make the most sense for people who plan to stay in the home long-term, ideally for the full life of the loan.
Does biweekly affect my mortgage interest tax deduction?
No significant impact. Mortgage interest is deductible as an itemized deduction, but most filers take the standard deduction ($16,100 single / $32,200 MFJ in 2026). For homeowners who do itemize, biweekly slightly reduces the annual mortgage interest deduction because you are paying less interest, which means a slightly smaller deduction. However, the actual interest savings far outweigh the lost tax deduction — for every $1 of "lost" deduction, you actually save $4-5 in interest you would have paid. The math always favors biweekly for itemizers.
Can I switch from monthly to biweekly at any time?
Usually yes, though the process varies by lender. Most lenders let you switch to biweekly through their online portal or by calling customer service. Some require a written request. Once enrolled, you typically need to authorize automatic withdrawals from your bank account, since biweekly payments are too frequent to make manually. You can also switch back to monthly at any time. Note that the savings are most dramatic when you start biweekly early in the loan — switching in year 25 of a 30-year loan provides minimal savings because most of the interest has already been paid.
What about a "weekly" mortgage payment program?
Some lenders offer weekly payment programs as well. Mathematically, weekly payments save slightly more than biweekly (about $5,000-10,000 more on a $400K loan) because principal is reduced more frequently. However, weekly programs are more complex to manage and the additional savings rarely justify the hassle. Biweekly captures about 95% of the benefit with much simpler administration.
Does paying biweekly hurt my credit score?
No, paying more frequently actually has no impact — credit reporting works on a monthly basis. Your servicer reports your loan status to the credit bureaus once per month. As long as you are not late, the frequency of your payments has zero effect on your credit score. There is also no benefit — paying biweekly does not boost your credit score, despite occasional marketing claims to the contrary.
Why do biweekly payments save so much?
Two effects compound: (1) the extra payment per year goes 100% to principal, which means the next month's interest is calculated on a smaller balance, and that smaller balance keeps shrinking interest charges for the rest of the loan; (2) reducing principal early in the loan has the largest impact because mortgage interest is front-loaded — for the first decade of a 30-year loan, most of your payment is interest, so any extra dollar of principal saves multiple dollars of future interest. The "13th payment" trick can save $90,000+ on a typical mortgage because of this exponential compounding.
Data sources: Freddie Mac Primary Mortgage Market Survey (PMMS), April 2, 2026 (30-year fixed 6.46%, 15-year fixed 5.77%); standard amortization formula.
Last updated: April 2026.
Disclaimer: Calculator results assume your lender accepts biweekly payments and applies them immediately rather than holding them in a suspense account. Always confirm your lender\'s biweekly policy in writing. The "extra monthly principal" approach produces equivalent savings without any setup or fees.