A biweekly mortgage payment strategy accelerates your payoff and saves thousands in interest—with minimal extra effort. This calculator shows exactly how much you'll save by switching from monthly to biweekly payments.
How This Calculator Works
This calculator compares monthly vs biweekly payment strategies:
- Loan Amount: Your mortgage principal
- Interest Rate: Your annual mortgage rate
- Loan Term: Original loan length (typically 30 years)
- Monthly Payment: Your current payment amount
- Biweekly Payment: Half your monthly payment, paid every two weeks
- Savings: Interest saved and time shaved off your loan
The Formula Explained
Monthly: 12 payments per year = 12 Ă— Payment
Biweekly: 26 half-payments per year = 26 Ă— (Payment/2) = 13 monthly equivalents
The magic: Biweekly payments result in one extra monthly payment per year, applied entirely to principal.
Step-by-Step Example
$350,000 Mortgage at 6.5% for 30 Years
| Method | Monthly Equivalent | Term | Total Interest |
| Monthly | $2,212 | 30 years | $446,000 |
| Biweekly | $2,396/mo avg | 24.7 years | $352,000 |
Savings: $94,000 in interest and 5.3 years earlier payoff!
Frequently Asked Questions
How does a biweekly mortgage work?
Instead of 12 monthly payments, you make 26 half-payments (every two weeks). Since there are 52 weeks in a year, you end up making the equivalent of 13 monthly payments instead of 12. That extra payment goes straight to principal, reducing your balance faster and shortening your loan.
Why does biweekly save so much money?
Two effects: (1) One extra payment per year reduces principal faster, (2) More frequent payments mean interest is calculated on a slightly lower balance between payments. The principal reduction is the main driver—extra payments early in the loan have outsized impact because they reduce future interest charges.
How much can I really save?
On a typical 30-year mortgage, biweekly payments save 4-6 years of payments and reduce total interest by 15-25%. The exact savings depend on your interest rate and loan amount. Higher rates and larger loans produce bigger dollar savings.
Do I need my lender to set up biweekly payments?
Not necessarily. Some lenders offer biweekly programs (sometimes with fees—avoid these). Alternatively, DIY approach: Make your regular monthly payment plus 1/12th extra toward principal each month. This achieves the same result without coordinating with your lender.
Are there fees for biweekly mortgage programs?
Some third-party services charge setup fees ($200-500) plus ongoing fees for biweekly programs. These are unnecessary! Either have your lender set it up for free, or simply make one extra payment annually yourself. Never pay fees for something you can do yourself.
Some loans have prepayment penalties—check your mortgage documents. Most conventional mortgages allow unlimited extra payments. If your loan penalizes prepayment, the penalty is often limited to the first few years. After that period, prepay freely.
Mathematically, they're nearly identical. Biweekly has a slight edge due to more frequent principal reduction. Practically, biweekly is easier to stick with because it's automatic. A lump-sum annual payment requires discipline to save and remember. Choose the method you'll actually follow.
When does biweekly NOT make sense?
Skip biweekly mortgage acceleration if: (1) You have high-interest debt (credit cards) to pay first, (2) You haven't maxed employer 401(k) match, (3) You lack an emergency fund, (4) Your mortgage rate is very low (under 3-4%) and you could invest the difference. Pay off expensive debt and invest before accelerating a cheap mortgage.
Key Points to Remember
- One extra payment yearly: That's the core benefit of biweekly
- DIY is free: Avoid services that charge fees
- Check for prepayment penalties: Rare but possible in some loans
- Automate it: Set up automatic payments so you don't have to think
- Prioritize wisely: Pay off high-interest debt first