Mortgage Recast Calculator
New payment and interest saved after a lump sum.
Enter your values
Enter the current balance in $.
Enter the interest rate in %.
Enter the months remaining you are working with.
Enter the lump sum payment in $.
Enter the recast fee in $.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- New monthly payment
- $1,781.11
- Monthly saving
- $329.83
- Current payment
- $2,110.94
- New balance
- $270,000.00
- Interest saved
- $98,700.41
- Payoff date
- unchanged — 300 months left
Quick answer
A recast re-amortises your loan over the remaining term after a lump-sum principal payment, lowering the monthly payment while keeping the same rate and payoff date.
new payment = P·r ÷ (1 − (1+r)^−n)
At a glance
| What it does | New payment and interest saved after a lump sum. |
|---|---|
| Category | Finance |
| Inputs needed | Current balance, Interest rate, Months remaining, Lump sum payment, Recast fee |
| Main output | New monthly payment |
| Formula | new payment = P·r ÷ (1 − (1+r)^−n) |
| Cost | Free — no sign-up, no download |
How to use the Mortgage Recast Calculator
- 1Enter your current balance, rate and months remaining.
- 2Enter the lump sum you plan to pay.
- 3Add the lender's recast fee, usually $150–500.
Inputs explained
- Current balance($)
- Enter the current balance in $.
- Interest rate(%)
- Enter the interest rate in %.
- Months remaining
- Enter the months remaining you are working with.
- Lump sum payment($)
- Enter the lump sum payment in $.
- Recast fee($)
- Enter the recast fee in $.
Worked example
Using the values the calculator loads with:
Inputs
- Current balance320000 $
- Interest rate6.25 %
- Months remaining300
- Lump sum payment50000 $
- Recast fee250 $
Results
- New monthly payment$1,781.11
- Monthly saving$329.83
- Current payment$2,110.94
- New balance$270,000.00
- Interest saved$98,700.41
- Payoff dateunchanged — 300 months left
Frequently asked questions
Is recasting better than refinancing?
Recasting keeps your rate and costs a few hundred dollars; refinancing changes the rate but costs thousands in closing fees.
Does a recast shorten the loan term?
No — it lowers the payment over the same remaining term. Keep paying the old amount if you want an earlier payoff.
What do I need to enter into the Mortgage Recast Calculator?
Just 5 values: current balance, interest rate, months remaining, lump sum payment, recast fee. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the Mortgage Recast Calculator work out the answer?
A recast re-amortises your loan over the remaining term after a lump-sum principal payment, lowering the monthly payment while keeping the same rate and payoff date. It applies the formula new payment = P·r ÷ (1 − (1+r)^−n) and shows the working so you can check each step by hand.
Is the Mortgage Recast Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.