Mortgage Payoff Calculator – Early Payoff & Extra Payments

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Mortgage Payoff Calculator

See exactly when your mortgage pays off — and how much faster you'd get there with extra monthly payments, an annual lump sum, or both. Interest savings calculated to the dollar, with side-by-side comparison. Free, instant, private.

✓ Extra Monthly · ✓ Annual Lump Sum · ✓ Savings Delta · ✓ Payoff Date Shift

🏠 Early Mortgage Payoff Estimator

🔧 JS ⏳ · Input — · Result — · Engine ⏳

Current balance ($)

Interest rate (%/yr)

Monthly payment ($)

Extra per month ($)

One-time lump sum ($) — optional

Extra each year ($, like a 13th payment) — optional

Start counting from

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PAYOFF IN

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Payoff date

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Total interest

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Months saved

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📊 Side-by-Side Comparison

	Scheduled	With your extra payments	Difference
Payoff	—	—	—
Total interest	—	—	—
Total paid	—	—	—

⚠️ Educational estimate using standard amortization. Real payoffs include escrow, per-diem interest at closing, and possible prepayment penalties — confirm with your servicer before scheduling a payoff.

How Does a Mortgage Payoff Calculator Work?

Every month, your payment first covers the month's interest — balance × annual rate ÷ 12 — and whatever remains reduces the principal. Because interest is charged on the remaining balance, every dollar of principal you kill early stops generating interest for every month that follows.

interest₁ = balance × rate ÷ 12
principal₁ = payment − interest₁   →   new balance = balance − principal₁   (repeat)

Worked example: a $240,000 balance at 6.5% accrues $1,300 of interest in month one. With a $1,800 payment, $500 hits principal. Add $200 extra and $700 hits principal — the loan now compounds in your favor. Simulating month by month (as this calculator does) gives the exact payoff month and total interest, including all your accelerations.

Three Ways to Pay Off Your Mortgage Early

Strategy	How it works	Best for
Extra monthly	Add a fixed amount to every payment — steady and automatic	Stable income; the set-and-forget approach
Annual lump sum	One extra payment a year (or apply your tax refund)	Bonus earners and the 13-payment fans
Lump sum now	A one-time principal reduction from savings, inheritance or a sale	Windfalls — the savings compound from day one

Biweekly half-payments (half the monthly amount every two weeks) produce the same effect as one extra monthly payment per year — 26 halves = 13 full payments. Enter one extra monthly payment equal to half your normal payment to see that scenario. Always confirm your servicer applies extra payments to principal, not the next month's payment — that single instruction makes the entire strategy work.

Why Use This Early Mortgage Payoff Calculator?

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Three Accelerators

Extra monthly, annual lump sums and one-time windfalls — combined or separate.

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Side-by-Side Delta

Scheduled vs accelerated payoff, interest and total — the savings, quantified.

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Exact Payoff Date

A real calendar month and year, not just "months remaining."

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100% Private

Balance and rate never leave your browser — nothing sent or stored.

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Instant & Offline

Every keystroke re-simulates the full loan — test five strategies in a minute.

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Month-by-Month Math

The simulation shows the actual amortization mechanics — no black box.

Popular Use Cases

• 🎯 See how $200 extra per month changes a 30-year mortgage's timeline
• 💵 Decide between investing a windfall and paying down principal
• 📅 Model the "13th payment" annual strategy before committing
• 📉 Compare payoff speed after a refinance to a shorter term
• 🏡 Plan debt-free-by-retirement against your target retirement date
• 🧾 Verify a servicer's quoted payoff timeline independently

Pro Tips for Paying Off Early

• Early extra payments are worth more: $100 extra in year 1 kills principal that would have generated interest for 29 more years — the same $100 in year 29 saves almost nothing. Front-load when you can.
• Check your prepayment penalty: most modern US mortgages have none, but verify in your note before large lump sums.
• Match extra dollars to their best use: if your mortgage rate is 3% but cards charge 22%, kill the cards first — then redirect those payments here.
• Keep the emergency fund sacred: extra principal is locked inside the house; don't strip your cash buffer to speed up equity.
• Retirement contributions usually win: at 7% average market returns versus a 6.5% mortgage, maxing retirement first is often the better expected value — this is math context, not personal advice.

Frequently Asked Questions

It simulates your loan month by month: interest is charged on the remaining balance, your payment (plus extras) covers that interest first and reduces principal with the rest, then the cycle repeats until the balance hits zero — reporting the total months and interest along the way.

Add extra to every payment, make one extra payment a year, or apply lump sums to principal. Instruct your servicer in writing that extra amounts go to principal reduction — otherwise some apply them as early payments for the next month, which saves nothing.

On a $240,000 balance at 6.5%, $200 extra per month typically cuts roughly 5–6 years off a 30-year loan and saves over $80,000 in interest. Enter your own numbers above — the side-by-side table shows your exact savings.

Paying one full extra monthly payment per year — via a lump sum or biweekly half-payments — effectively turns a 30-year loan into roughly a 24-year loan. Enter the extra amount in the "Extra each year" box to model it precisely for your balance and rate.

No — it models principal and interest only, which is the part that compounds. Escrow (taxes/insurance), PMI and fees ride alongside and don't affect the payoff math. Enter just your P&I payment, not your full escrowed bill.

It's a risk-adjusted comparison: extra principal earns a guaranteed return equal to your mortgage rate, while investments may earn more (with volatility and tax). High mortgage rate → payoff looks strong; low rate plus untapped retirement accounts → investing often wins. A fiduciary advisor can personalize it.

Then the balance grows (negative amortization) and no payoff date exists. If the simulation can't reach zero within 1,200 months, the tool tells you the payment is below the interest accrual — you'd need a higher payment or a loan modification.

No. The simulation is JavaScript in your browser — balance, rate and payments never leave your device. Refreshing clears everything.