Mortgage Payoff Calculator

Enter your current balance, rate, and monthly payment. Add extra monthly, yearly, or one-time payments to see total interest saved, months eliminated, and your exact new payoff date.

Extra Payment Options

Guides & Reference

How It Works

Extra Monthly PaymentsCommitting a fixed extra amount each month

Enter your balance, rate, and required payment, then add an extra monthly amount. The calculator runs two simulations — original schedule and with-extra schedule — and shows interest saved, months eliminated, and new payoff date. Every dollar of extra payment goes directly to principal, eliminating all future interest on that amount. Example: $280,000 at 6.5%, adding $300/month extra saves $54,000 and pays off 8 years early.

Extra reduces principal → less balance → less interest → earlier payoff$280k, 6.5%, +$300/mo: save $54,000, payoff 8yr early
Lump Sum PaymentApplying a bonus, tax refund, or inheritance

Enter a one-time payment amount. It reduces the balance immediately, saving all future interest on that principal from day one. A $20,000 lump sum on a $280,000 mortgage at 6.5% saves approximately $31,000 in total interest. The calculator also shows the breakeven point: how many months until interest savings exceed the lump sum amount.

Lump sum eliminates interest on that principal for all remaining months$20k lump sum on $280k at 6.5%: saves ~$31,000 total interest
Bi-Weekly Payment PlanMaking 26 half-payments instead of 12 full payments

Enter extra monthly payment equal to one-twelfth of your monthly payment to simulate bi-weekly. This creates 13 full payments per year instead of 12. The extra annual payment reduces principal every year. On a 30-year $300,000 mortgage at 6.5%: saves about $55,000 and 5 years vs monthly payments. Most servicers accept this labeled as principal prepayment.

Bi-weekly: 26 half-payments = 13 full payments per year$300k, 6.5%, 30yr: bi-weekly saves $55k, 5yr early payoff
Combined StrategyMaximum payoff speed using all extra payment types

Enter extra monthly amount, extra annual amount, and one-time lump sum together. The calculator applies all three simultaneously. For maximum impact: apply a lump sum immediately, commit to a monthly extra within budget, and direct year-end bonuses as the annual extra. Every dollar applied earlier in the loan saves more than the same dollar applied later.

Lump sum + monthly extra + annual extra → maximum interest savedAll three together: compounding savings from every direction
Opportunity CostPrepay mortgage vs invest the difference

Prepaying a 6.5% mortgage gives a guaranteed 6.5% after-tax return. Stock market historical average is 7-10%/yr with volatility and no guarantee. Financial consensus: max your 401k match first (immediate 50-100% return), pay off high-rate debt, build an emergency fund — then choose between prepayment and investing based on your mortgage rate and risk tolerance.

Guaranteed mortgage rate vs expected investment returnAt 6.5% mortgage: investing likely beats prepaying at 7%+ expected returns

Quick Reference

Verify these in the calculator above.

Monthly extra

$280k, 6.5%, +$300/mo extra

Save $54k, 8yr early

Bi-weekly

$300k, 6.5%, 30yr bi-weekly

Save $55k, 5yr early

Lump sum

$20k lump sum on $280k, 6.5%

Save ~$31k total

Small extra

$100/mo extra on $300k, 6.5%

Save $23k, 2.5yr early

Early timing

Year 1 extra $1 saves

~$3.80 total interest

Late timing

Year 20 extra $1 saves

~$1.27 total interest

Bi-weekly

Bi-weekly extra payments/yr

1 extra full payment

Label rule

Label all extra payments as

"Additional principal"

Tips & Shortcuts

Always label extra payments as "additional principal" in your servicer portal — without this label, some servicers credit the extra to future months instead of reducing your balance today.

The highest ROI for extra payments is in the first 10 years, when most of each payment is interest and the balance is largest. A dollar applied in year 1 saves roughly 3x more than the same dollar in year 20.

Check your loan documents for prepayment penalties — some mortgages (especially older or non-conforming loans) charge fees for large lump sum payments in the first few years.

Bi-weekly payment services offered by third parties charge unnecessary fees. Accomplish the same by making one extra full monthly payment per year, labeled as principal, directly to your servicer.

If your mortgage rate is below 4%, investing the extra money likely builds more long-term wealth than prepaying. The opportunity cost calculation shifts significantly at lower mortgage rates.

Common Mistakes

Sending extra payment without specifying principal

Without the "additional principal" label, many servicers apply the extra to your next scheduled payment rather than reducing your balance. The result looks like a credit on your account but does not save interest. Always verify on your next statement.

Expecting the monthly payment to drop after extra payments

Fixed mortgages keep the required payment the same regardless of extra payments. If you want a lower payment after paying down the balance, ask your servicer about a recast — typically $200-300, it recalculates the payment on the reduced balance.

Making extra payments in the last 5 years of the loan

By year 25 of a 30-year mortgage, most of your payment is already principal. Extra payments late in the loan save very little interest. The same dollar applied in year 5 saves roughly 4-5x more than in year 25.

Prepaying before maxing out the 401k employer match

Employer match is an immediate 50-100% guaranteed return. Paying down a 6.5% mortgage before capturing the full employer match is like turning down free money. Always max the match before any extra mortgage payments.

Not checking for prepayment penalties

Some loans — particularly those originated before 2010 or non-conforming jumbo loans — carry prepayment penalties for the first 3-5 years. Read your loan documents or call your servicer before making a large lump sum payment.

Frequently Asked Questions

On a $300,000 mortgage at 6.5% with 25 years remaining, $200 extra per month saves about $42,000 in interest and pays off roughly 4.5 years early. Enter your actual balance and rate for a precise result.

Breakeven = lump sum / monthly interest saved. A $10,000 lump sum on a 6.5% mortgage saves about $54/month initially — breakeven is around 185 months. Total interest saved far exceeds the lump sum over the remaining loan life.

Yes. 26 half-payments per year = 13 full payments vs 12 monthly. The extra annual payment goes directly to principal. On $300,000 at 6.5% for 30 years: saves $55,000 and cuts 5 years off the loan.

Compare rates. Prepaying a 6.5% mortgage gives a guaranteed 6.5% return. If investments are expected to return more, investing wins. Priority: 401k match first, high-rate debt, emergency fund — then decide between prepayment and investing.

No — fixed-rate mortgages keep the required payment the same. Extra payments shorten the term. A recast ($200-300 fee) can recalculate the payment on the reduced balance if you want a lower required payment.

Specify extra payments as "additional principal" in your servicer portal. Without this label, some servicers credit the extra to future months instead of reducing the balance. Always verify on the next statement.

When expected investment returns exceed your mortgage rate, when you lack an emergency fund, carry high-rate debt, or have not yet captured the full 401k employer match. All of these alternatives beat prepaying a sub-7% mortgage.

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