Recast
Lower payment, same rate & payoff date
- New payment
- Monthly savings
- Total interest left
- Payoff
Free · instant · no sign-up
Mortgage Recast Calculator
Put a lump sum toward your mortgage and see your new lower payment instantly — then compare it against paying the same amount as extra principal or refinancing. One clear answer, with the chart to prove it.
Your payment today: /mo
Bottom line
Extra principal
Same payment, pay off early
- Payment
- Time saved
- Total interest left
- Payoff
Refinance
New rate, new loan, closing costs
- New payment
- Monthly savings
- Break-even
- Total interest left
Estimates for education only — not financial advice. Recast fees, minimums, seasoning, and eligibility vary by servicer, loan type, investor, and state. Government loans (FHA/VA/USDA) generally can't be recast. Confirm your numbers with your servicer.
What a mortgage recast actually does
A recast (also called re-amortization) is simple: you make one large payment toward your principal, and your lender recalculates your monthly payment over the same remaining term at the same interest rate. Your rate doesn't change. Your payoff date doesn't change. Only your monthly payment drops — because a smaller balance is spread across the same number of payments.
That's what makes recasting the quiet favorite of homeowners sitting on a low locked-in rate: you lower your payment without giving up your rate the way a refinance would.
Recast vs extra principal vs refinance
Your lump sum can go three ways, and they optimize different things:
| Option | Monthly payment | Payoff date | Total interest | Upfront cost |
|---|---|---|---|---|
| Recast | Lower ✓ | Unchanged | Higher | ~$150–$500 fee |
| Extra principal | Unchanged | Sooner ✓ | Lowest ✓ | $0 |
| Refinance | Depends on rate | Resets | Depends on rate | ~2–6% closing costs |
The key insight most calculators hide: the same lump sum as extra principal always costs less total interest than recasting — because you keep making the higher payment and finish early. Recasting trades that lifetime saving for lower monthly cash flow today. Neither is "wrong"; it depends on whether you need breathing room in your budget or the cheapest possible payoff. The calculator above shows both, plus a refinance leg if you add today's rate.
How to use the calculator
- Enter your balance, rate, and years left. These come straight off your latest statement.
- Enter the lump sum you're thinking of applying, and your servicer's recast fee if you know it.
- Optionally add a refinance — today's rate, term, and closing costs — to see all three paths compared, with an amortization chart of how fast each one reaches $0.
Is recasting worth it?
Recasting tends to win when you're holding a rate below today's market, you want a lower payment, and you have a chunk of cash from a bonus, inheritance, or home sale. It's cheap ($150–$500 vs thousands in refinance costs), keeps your rate, and requires no appraisal or credit check. Read the full breakdown in is recasting worth it?, compare it head-to-head in recast vs refinance, and check your servicer's rules on our lender policy pages.
Frequently asked questions
What is a mortgage recast?
A recast is when you make a large one-time payment toward your principal and your lender re-amortizes the loan — recalculating your monthly payment over the same remaining term at the same interest rate. Your rate and payoff date stay the same; only the monthly payment goes down.
Does recasting lower my monthly payment?
Yes. Because a smaller balance is spread over the same number of remaining payments at the same rate, your required monthly payment drops. That is the main reason people recast — it improves monthly cash flow without refinancing.
Is recasting better than just paying extra principal?
They do different things. The same lump sum as extra principal (while keeping your current payment) always pays off the loan sooner and costs less total interest — but it does not lower your required payment. Recasting lowers your payment but keeps the long term, so you pay more interest overall. Choose recast for lower monthly cash flow; choose extra principal to get out of debt cheapest. This calculator shows you both side by side.
Recast vs refinance — which is cheaper?
Recasting keeps your existing (often lower) interest rate and costs a small fee, usually $150–$500. Refinancing replaces your loan at today's rate with closing costs of roughly 2–6% of the balance, and only wins if the new rate is low enough to beat the break-even. If your current rate is already low, recasting is almost always cheaper.
How much does a recast cost, and what is the minimum?
Recast fees are commonly $150–$250 (a few large banks are reported fee-free), and the minimum lump sum is usually $5,000–$10,000, though some servicers require about 10% of the balance. Exact figures vary — see our lender pages and always confirm with your servicer.
Which loans can be recast?
Conventional (Fannie Mae / Freddie Mac) loans are usually eligible. Government loans — FHA, VA and USDA — generally cannot be recast. Jumbo and portfolio loans vary by servicer. Interest-only and Option ARM loans are typically ineligible.
Does recasting change my interest rate or extend my loan?
No. A recast keeps your exact interest rate and your original payoff date. It only recalculates the monthly payment on the smaller balance. That is what makes it attractive to homeowners holding a low locked-in rate.
Is the recast estimate here exact?
It uses standard amortization math and is accurate for planning, but your servicer's figures are what bind. Fees, minimums, seasoning rules, and effective dates vary. Treat this as an educational estimate and confirm the final numbers with your lender.