1
Enter your current mortgage balance
Use the remaining principal balance, interest rate, and years left on the loan.
Mortgage recast calculator
Free Mortgage Recast Calculator
A mortgage recast calculator estimates your new monthly payment after you make a lump-sum principal payment and your lender recalculates the payment across the remaining term.
New payment
$1,688.02
Monthly savings
$337.60
Interest savings
$51,281.08
Calculator inputs
Model a principal recast
Current mortgage
The loan terms your lender would use before the recast.
Recast request
The principal reduction and fee for the lower-payment request.
Results
$2,025.62 to $1,688.02
The lump-sum payment lowers the loan balance to $250,000.00 and reduces the required monthly payment by $337.60.
New loan balance
$250,000.00
Principal payment
$50,000.00
Interest before recast
$307,686.45
Net savings after fee
$51,031.08
Payment impact
Savings snapshot
Monthly payment reduction
$337.60Lower required payment after lender approval.
Total interest saved
$51,281.08Interest avoided from the lower principal balance.
Recast fee payback
1 monthHow long monthly savings take to cover the fee.
Quick guidance
Recast versus refinance
A recast is usually a payment reset on the same mortgage. It can be useful when the existing rate is good and the goal is lower required monthly cash flow, not a new loan.
Plan a friendly loan2
Add your lump-sum principal payment
Enter the amount you plan to apply directly to principal plus any lender recast fee.
3
Compare the old and new payment
Review monthly savings, annual savings, interest savings, and how quickly savings cover the recast fee.
FAQ
Mortgage recast questions
What is a mortgage recast calculator?
A mortgage recast calculator estimates the new monthly payment after you make a lump-sum principal payment and your lender recalculates the payment over the remaining loan term.
How is a mortgage recast different from refinancing?
A recast keeps the same loan, interest rate, and payoff date. Refinancing replaces the loan with a new mortgage and may change the rate, term, closing costs, and underwriting requirements.
Does recasting a mortgage save interest?
Yes, the lump-sum principal payment can reduce future interest because the remaining balance is lower. The recast itself mainly lowers the required monthly payment.
When does a mortgage recast make sense?
A recast can make sense when you have cash to reduce principal, want a lower payment, and already have a favorable interest rate you do not want to refinance away.