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Printed July 8, 2026 · https://trycleartally.com/mortgage-recast-calculator
Estimates for educational purposes only — not financial advice. See https://trycleartally.com/disclaimer.
Mortgage Recast Calculator
A mortgage recast puts a lump sum toward your principal and re-amortizes the loan, lowering your monthly payment without refinancing. See your new payment, the interest saved, and how it compares with simply prepaying.
Reviewed by the ClearTally editorial team · Last updated July 8, 2026 · Methodology & sources
A recast keeps this the same — only the payment changes.
Servicers often require a minimum, commonly $5,000–$10,000.
Editable estimate — servicers commonly charge a few hundred dollars.
New monthly payment after recast
$1,688.02
Down from $2,025.62 — same rate, same payoff date
Monthly payment relief
$337.60
Interest saved
$51,281
$51,031 net of the $250 fee
Payoff date
Unchanged
A recast lowers the payment — it never shortens the term.
The alternative: same lump sum, keep your old payment
Skip the recast, send the lump sum to principal, and keep paying $2,025.62 — the loan ends sooner and saves more interest, but your required payment never drops.
Paid off sooner
7 yrs 11 mo
Done in 17 yrs 1 mo instead of 25 yrs 0 mo
Interest saved this way
$143,646
$92,365 more than the recast
Three paths for the same loan
Assumes your servicer allows recasting — most conventional loans qualify, while FHA, VA, and USDA loans typically don't — and that the lump sum meets their minimum. The fee is an editable estimate. Principal & interest only. Estimate only, not financial advice.
Mortgage Recast Worksheet
New monthly payment after recast
$1,688.02
Assumes the servicer allows recasting (FHA/VA/USDA loans typically don't). Fee and minimums vary. Principal & interest only. Not financial advice.
Balance by year (original vs recast vs old payment kept)
| Year | No lump sum | Recast | Old payment kept |
|---|---|---|---|
| 1 | $295,047 | $245,872 | $241,698 |
| 2 | $289,762 | $241,468 | $232,840 |
| 3 | $284,123 | $236,769 | $223,389 |
| 4 | $278,106 | $231,755 | $213,305 |
| 5 | $271,686 | $226,405 | $202,546 |
| 6 | $264,837 | $220,697 | $191,066 |
| 7 | $257,529 | $214,607 | $178,817 |
| 8 | $249,731 | $208,109 | $165,748 |
| 9 | $241,411 | $201,176 | $151,803 |
| 10 | $232,534 | $193,778 | $136,925 |
| 11 | $223,062 | $185,885 | $121,050 |
| 12 | $212,957 | $177,464 | $104,112 |
| 13 | $202,174 | $168,478 | $86,040 |
| 14 | $190,669 | $158,891 | $66,757 |
| 15 | $178,393 | $148,661 | $46,183 |
| 16 | $165,296 | $137,747 | $24,232 |
| 17 | $151,321 | $126,101 | $810 |
| 18 | $136,411 | $113,676 | $0 |
| 19 | $120,501 | $100,418 | $0 |
| 20 | $103,527 | $86,272 | $0 |
| 21 | $85,415 | $71,179 | $0 |
| 22 | $66,091 | $55,076 | $0 |
| 23 | $45,472 | $37,894 | $0 |
| 24 | $23,473 | $19,561 | $0 |
| 25 | $0 | $0 | $0 |
Calculated using the standard formulas described at https://trycleartally.com/methodology — for educational estimates only, not a quote or financial advice. Verify with your lender or financial institution before making decisions.
Not sure a recast is the right lever? Compare it with refinancing into a new rate or steady extra payments toward principal.
How it works
Recasting is the mortgage move most homeowners have never heard of. You make one large principal payment, your servicer charges a small processing fee, and then recalculates your required payment from the smaller balance over the same remaining term at the same rate. Nothing else about the loan changes — no new application, no credit check, no appraisal, no closing costs. Your payoff date stays put; your required payment drops.
The comparison that matters is with just prepaying: send the same lump sum without a recast, keep making your old payment, and the loan ends years earlier with a bigger interest saving. The recast trades some of that saving for breathing room in the monthly budget. This tool shows all three paths — do nothing, recast, or prepay and keep the payment — so the tradeoff is visible in dollars.
Example: a $300,000 balance at 6.5% with 25 years left has a payment of about $2,026. Recast with a $50,000 lump sum and the payment drops to about $1,688 — roughly $338 a month of relief — while lifetime interest falls by about $51,300 (about $51,000 after a $250 fee). Put the same $50,000 in but keep paying $2,026, and instead the loan ends 7 years 11 months early, saving about $143,600 in interest.
Sources & further reading
FAQ
A recast (or re-amortization) is when your servicer recalculates your monthly payment after a large principal payment, spreading the smaller balance over the remaining term at your existing rate. The loan itself doesn't change — same rate, same payoff date, same lender. What changes is the required payment, which drops in proportion to the balance you paid off. Regular extra payments don't do this: they shorten the loan but leave the required payment untouched. Recasting is the only way to lower the payment without replacing the loan.