Mortgage Recast Calculator
Calculate how much you can slash your monthly mortgage payment by recasting your loan. Unlike a full refinance, a mortgage recast preserves your existing low interest rate and remaining loan term while re-amortizing your balance following a lump-sum principal curtailment.
Remaining principal loan balance reported on your latest mortgage statement
Lump-sum cash paid directly toward principal (typically $5,000+ required by lenders)
Years left on your current mortgage amortization schedule
Locked interest rate of your current mortgage promissory note
One-time administrative processing fee charged by loan servicer (typically $150–$350)
New lower monthly principal and interest payment
How to Use This Calculator
- Enter your current unpaid loan balance from your mortgage statement.
- Enter the lump-sum cash amount you plan to pay toward principal.
- Enter remaining loan term years and your locked note interest rate.
- Input your servicer administrative recast fee (usually $250).
- Review your immediate monthly payment reduction and lifetime interest savings.
Formula & Calculation Methodology
Unlike making an extra principal payment (which only shortens loan duration), a mortgage recast formally re-calculates monthly amortization over the exact remaining term, immediately lowering required monthly cash flow.
Worked Example
$320,000 balance with 25 years remaining at 5.75% recasting with a $50,000 lump sum
Frequently Asked Questions
How does recasting differ from refinancing?↓
Refinancing replaces your existing mortgage with a new loan, requiring a new credit check, home appraisal, title search, and $4,000 to $8,000 in closing costs. Recasting keeps your existing loan, rate, and term for a nominal $150 to $350 fee.
Do all mortgage loans qualify for recasting?↓
Most conventional conforming loans (Fannie Mae and Freddie Mac) permit recasting. However, FHA, VA, and USDA government-backed loans generally do not permit recasting under federal program rules.
How much lump-sum cash is required to request a recast?↓
Most mortgage servicers (e.g. Chase, Wells Fargo, Rocket) establish a minimum lump-sum requirement between $5,000 and $10,000 or 10% of the remaining balance.
What limitation should I know about loan term length after a recast?↓
A recast does not shorten your loan maturity date; if you have 25 years remaining, your term remains 25 years. If your primary goal is paying off the mortgage faster rather than reducing monthly obligations, making extra principal payments without recasting achieves faster payoff.
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Source Citation & Disclaimer
Informational tool only; not licensed tax, legal, or financial advice.