What it means
Paying down principal early usually shortens the loan or leaves the payment unchanged. A recast takes a third route: after a lump-sum payment, the lender re-amortises the smaller balance over the remaining term and the monthly payment drops.
The appeal is cheapness. Where refinancing replaces the whole loan with new fees and a new rate, a recast keeps the existing rate and term intact and typically costs a small administrative fee, often a few hundred dollars.
The catch is availability. Lenders offer recasting at their discretion, usually require a minimum lump sum, and government-backed programmes set their own rules, so the option must be requested and confirmed rather than assumed.
Recasting fits specific moments. A borrower who sells an old home after buying a new one, receives an inheritance, or lands a bonus can park the lump sum in the mortgage and immediately ease the monthly obligation without disturbing a favourable rate.
Adjustable-rate loans have their own version. The Consumer Financial Protection Bureau's handbook on adjustable-rate mortgages explains how such loans periodically recalculate payments, a scheduled recast that can raise payments as well as lower them.
For a business owner with lumpy income, the recast is a useful valve. Windfalls can be converted into permanent monthly relief at trivial cost, improving cash flow resilience without the ordeal and expense of refinancing.
Investment accounts hold the mirror-image idea. Just as a lump sum recast lowers a payment, a lump-sum withdrawal can force a payment plan to be reworked, and lenders treat large unapproved changes with equal ceremony.
Some lenders limit how often a loan can be recast, so the lump sum is best deployed once, decisively, rather than in a series of small recasts that exhaust the allowance.
In practice
Real-world examples.
Example
A consultant banks a 90,000 bonus and pays it against her 320,000 mortgage. The recast drops her payment by roughly 400 a month, and her variable-income household breathes easier.
Example
A couple buys a new home before selling the old one. When the sale completes, they recast with the 150,000 proceeds, cutting the payment by a third while keeping their low fixed rate.
Example
A borrower assumes his lump sum will lower his payment automatically. It shortens the term instead, and only a phone call and a formal recast request produce the monthly relief he wanted.
Formula
Calculation
New payment re-amortises the reduced balance over the remaining term at the existing rate. Payment = balance x (monthly rate) / (1 - (1 + monthly rate)^-months remaining).
Worked example. A $300,000 balance at 5% with 20 years left costs about $1,980 a month. After a $60,000 lump sum and recast, $240,000 on the same terms costs about $1,584, a saving of $396 a month. Total interest over the remaining 240 months falls from about $175,200 to about $140,100, because the smaller balance accrues less interest. A $250 recast fee is recovered in under one month of the saving, whereas a refinance could cost thousands in fees and a different rate.Case study
Seen in the real world.
In this illustrative fictional case, Yusuf, who owns a seasonal tourism business, carries a mortgage fixed at a rate far below today's market. A strong season leaves him with 120,000 of surplus cash, and his bank suggests refinancing into a new loan at a rate two points higher. His accountant spots the better move: a recast keeps the old rate, applies the lump sum, and cuts the payment by about 700 a month for a 250 fee. The lower fixed outflow steadies the business through the off-season, and the old rate, now unrepeatable, stays untouched. Yusuf's note to fellow owners is that when rates have risen since you borrowed, the mortgage you have is an asset, and a recast improves it where refinancing would destroy it.
Watch out
Common mistakes.
- Assuming any extra payment lowers the monthly amount, when standard overpayments shorten the term instead, and only a formal recast reduces the payment.
- Refinancing when a recast would serve, when keeping a below-market existing rate is worth far more than new-loan features, and the recast fee is trivial by comparison.
- Failing to confirm eligibility first, when lenders set minimum lump sums, exclude some loan types, and require the borrower to request the recast explicitly.
Questions
People also ask.
How does a mortgage recast work?
You pay a lump sum against principal, and the lender re-amortises the reduced balance over the remaining term at the existing rate. The monthly payment falls while rate and term stay unchanged.
What does a recast cost?
Usually a small administrative fee, often a few hundred dollars, compared with the thousands a refinance costs. The trade is that recasting keeps your current rate rather than shopping for a new one.
Recast or refinance: which is better?
Recast when your existing rate is attractive and you want a lower payment cheaply. Refinance when market rates beat your current one or you need to change the loan's structure. Availability of recasting varies by lender and loan type.
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