Does making bi-weekly mortgage payments help?

Bi-weekly payments create 13 full payments each year, which shortens the payoff timeline. Enter an equivalent monthly extra payment in the calculator to quantify the impact.

🏡 Payoff Planning Last updated 3 Nov 2025 EEAT aligned

Mortgage Payoff Calculator

Model extra principal payments to see how quickly you can retire your mortgage. Compare the standard payoff timeline with your accelerated plan, quantify interest savings, and visualize the difference.

Author: Pawan, M.Tech (Data Science)
Reviewed by: CalcArena Finance Desk
Applicable Regions: Worldwide (USD example)

Enter your payoff plan

We compare your current payment against a plan with extra principal to show the payoff date, interest saved, and timeline reduction. All math stays in your browser.

Remaining loan balance

Outstanding principal today. Include any financed closing costs.

Annual interest rate (APR)

Use your loan's nominal APR. Adjustable-rate loans require recomputation after each reset.

Current monthly payment

Enter your regular scheduled payment (principal + interest). Exclude escrow for taxes and insurance.

Extra monthly principal

Amount you plan to add toward principal each month. Set to 0 to see the baseline payoff.

Payoff with extra

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Interest saved

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Time saved

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Baseline payoff time	—
Payoff with extra	—
Interest (baseline)	—
Interest (with extra)	—
Interest saved	—
Total extra paid	—

Timeline comparison chart

Hover to compare outstanding balance and cumulative interest with and without your extra payments.

Balance with extra payments

Balance with scheduled payments

Cumulative interest (extra plan)

Mortgage payoff TL;DR

Applying $200 extra principal each month on a $300,000 balance at 5.5% APR reduces your payoff time from 30 years 2 months to 23 years 6 months. You save $80,681 in lifetime interest while keeping the same lender-issued payment schedule.

How to use this calculator

Enter your remaining loan balance directly from your latest mortgage statement.
Provide the current interest rate (APR) for the mortgage—use the contractual rate, not an introductory teaser.
Type the scheduled monthly payment shown on your statement (principal + interest only).
Add the extra amount you can commit each month toward principal; leave at 0 to study the baseline.
Review the new payoff time, interest saved, and chart to confirm the plan meets your goals.

Formula & variables

n = -ln(1 - (B × i)/PMT) ÷ ln(1 + i)

B: Outstanding principal balance today.
i: Periodic interest rate (APR ÷ 12).
PMT: Monthly payment applied to the loan (scheduled + extra principal).
n: Number of remaining monthly payments.

The payoff formula assumes a fully amortizing loan. Extra principal increases PMT, which reduces the number of payments required to drive the balance to zero. The calculator switches to a simple division (B ÷ PMT) if the rate is 0%, ensuring mathematically stable results.

Worked example

Rounded to two decimals; actual calculations keep full precision.

Input	Value
Remaining balance (B)	$300,000
APR	5.50%
Scheduled payment	$1,700.00
Extra monthly principal	$200.00

1. Monthly rate i = 5.5% ÷ 12 = 0.004583.

2. Baseline payoff months n₀ = -ln(1 - (300,000 × 0.004583) / 1,700) ÷ ln(1.004583) ≈ 362 months (30 years 2 months).

3. Accelerated payment PMT₁ = 1,700 + 200 = 1,900.

4. New payoff n₁ = -ln(1 - (300,000 × 0.004583) / 1,900) ÷ ln(1.004583) ≈ 282 months (23 years 6 months).

5. Baseline interest ≈ 1,700 × 362 − 300,000 = $315,096.

6. Accelerated interest ≈ 1,900 × 282 − 300,000 = $234,415.

7. Interest saved = $315,096 − $234,415 = $80,681.

Edge cases checked

If the scheduled payment is less than the monthly interest (PMT ≤ B × i), the calculator warns that the loan will never amortize.
Zero APR triggers the simple payoff formula n = B ÷ PMT so results stay finite.
Negative or zero balances return immediate payoff with zero months and zero interest.

Key assumptions

Payments are made monthly at the end of each period (ordinary annuity assumption).
The interest rate stays fixed; recast when an adjustable-rate loan resets.
Extra payments are applied directly to principal without prepayment penalties.
Escrow for taxes/insurance is excluded; model those separately.
The calculator is educational; confirm payoff implications with your lender.

Underlying concepts

Accelerated amortization

Extra principal lowers the outstanding balance faster than scheduled amortization, reducing the interest accrued in subsequent periods. The effect compounds, which is why even modest extra payments can remove years from the payoff horizon.

Opportunity cost

Paying extra on a mortgage delivers a guaranteed return equal to the loan’s interest rate. Compare this to alternative investments—if you can reliably earn more elsewhere after taxes, it may be worth investing the surplus instead.

Frequently asked questions

Does making bi-weekly payments help? +

Yes. Paying half the monthly amount every two weeks results in 26 half-payments (13 full payments) per year. The calculator’s extra payment field can approximate this by adding one extra monthly payment divided across 12 months.

Will my lender charge a prepayment penalty? +

Most modern U.S. mortgages allow extra principal without penalty, but check your note or call your servicer. Some older loans or investment-property mortgages still include prepayment clauses.

Should I invest instead of paying extra on my mortgage? +

Compare your after-tax mortgage rate with the expected return of your investments. Paying down a 5% mortgage is equivalent to earning a risk-free 5% return; if you can earn more with acceptable risk, investing could be better.

References

About this calculator

Built by the CalcArena Finance Desk using trusted amortization formulas and audited for EEAT compliance. Use as planning guidance; confirm payoff strategies with your lender or advisor.

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