Mortgage Recast Calculator — Lower Your Payment Without Refinancing
See how much a lump-sum principal payment lowers your monthly mortgage payment via recasting — same rate, same payoff date, no refinance.
Recast fee pays for itself in ≈1 month.
Monthly Payment = Principal × [r(1+r)ⁿ] ÷ [(1+r)ⁿ − 1], where r is the monthly interest rate and n is the number of remaining payments. Recasting keeps your original rate and payoff date — only the payment is recalculated on the reduced balance. FHA, VA, and USDA loans are generally not eligible for recasting; conventional loans (including jumbo and Fannie Mae/Freddie Mac loans) usually are.
Reference Values
Last verified:| Category | Range | What It Means | Status |
|---|---|---|---|
| Typical minimum lump sum required | $5,000+ | Most lenders require a minimum principal paydown to approve a recast — varies by servicer. | Good |
| Typical recast fee ★ | ≈$150–$500 | A one-time administrative fee, far less than refinance closing costs. | ★ Best |
| Loan term after recast | Unchanged | Recasting keeps your original payoff date and interest rate — only the monthly payment is recalculated. | Good |
| Eligible loan types | Conventional (incl. jumbo, Fannie/Freddie) | FHA, VA, and USDA loans are generally NOT eligible for recasting. | Okay |
| Refinance closing costs (for comparison) | 2–6% of loan balance | What you'd pay instead if you refinanced rather than recast — recasting has no appraisal, credit check, or closing costs. | Poor |
Source: Mortgage recast mechanics, eligibility, and typical fee ranges aggregated from Bankrate and standard mortgage-servicer recast policies.
Worked Examples
$50,000 Lump Sum on a $300,000 Balance
- Remaining Balance
- $300,000
- Rate
- 6.0%
- Remaining Term
- 25 years
- Lump Sum
- $50,000
Same rate and remaining term, but the payment is recalculated on the new $250,000 balance instead of $300,000 — the payoff date doesn't change, only the monthly payment.
Small Lump Sum, Minimal Impact
- Remaining Balance
- $300,000
- Rate
- 6.0%
- Remaining Term
- 25 years
- Lump Sum
- $10,000
A smaller lump sum still lowers the payment, but proportionally less — recasting rewards larger principal paydowns.
How to Use This Calculator
- 1
Enter your current remaining balance, rate, and remaining term
From your latest mortgage statement.
- 2
Enter the lump-sum payment you're considering
The amount you'd pay toward principal to trigger the recast.
- 3
Enter the recast fee, if known
Optional — most lenders charge a small one-time fee, often $150–$500.
- 4
Compare your current and new payment
Shows your monthly savings and how quickly the recast fee pays for itself.
What Each Value Means
- New Payment After Recast ($/month)
- Your recalculated monthly payment based on the reduced principal balance, same interest rate, and same remaining term.
- Monthly Savings ($/month)
- The difference between your current payment and your new, recast payment.
Related Calculators
Frequently Asked Questions
What is mortgage recasting?
How is mortgage recasting different from refinancing?
What loans are eligible for recasting?
Is there a minimum lump sum required to recast?
Does recasting save me money on total interest paid?
References & Sources
- [1] Consumer Financial Protection Bureau — Mortgage Servicing (opens in new tab)
Supports: Evidence used for mortgage recast glossary: recasting, reamortization & more, including related formulas, definitions, or reference values.
Verified
- [2] Fidelity — What Is a Mortgage Recast and How Do You Do One (opens in new tab)
Supports: Evidence used for mortgage recast glossary: recasting, reamortization & more, including related formulas, definitions, or reference values.
Verified