Key takeaways
- Fee break-even = recast fee ÷ monthly payment drop. With a meaningful lump sum, that's usually only a few months.
- The bigger question is whether the money is better used elsewhere, such as an emergency fund or higher-interest debt.
- Prepaying without recasting saves more interest. Recast when a lower required payment matters more to you.
A recast is cheap, and the fee pays for itself quickly in most cases. Whether it's worth it is a bigger question: is putting a lump sum into your house the best use of that money, and do you want a lower payment more than an earlier payoff? This guide covers the fee break-even and then the questions that matter more.
The fee break-even
The simplest test: divide the recast fee by how much your monthly payment drops. That's how many months of lower payments it takes to earn the fee back.
Break-even (months) = recast fee ÷ monthly payment drop
Using a $320,000 balance at 6.5% with 27 years left (a payment of about $2,098), here's how the drop and break-even change with the lump sum:
| Lump sum | New payment | Monthly drop | Break-even, $250 fee | Break-even, $500 fee |
|---|---|---|---|---|
| $5,000 | $2,065 | $33 | 8 months | 16 months |
| $10,000 | $2,032 | $66 | 4 months | 8 months |
| $25,000 | $1,934 | $164 | 2 months | 4 months |
| $50,000 | $1,770 | $328 | 1 month | 2 months |
| $100,000 | $1,442 | $656 | 1 month | 1 month |
At this rate and term, every $10,000 you put down lowers the payment by about $66 a month. Unless the lump sum is small and the fee is high, the fee is rarely the deciding factor. Plug in your own numbers in the calculator.
The bigger question: where else could the money go?
Paying down a mortgage earns you, in effect, your loan's interest rate, guaranteed: every dollar of principal you pay off stops costing you interest at that rate. On a 6.5% loan, that's a solid, risk-free return. On a 3% loan, it's a much lower bar.
Things people commonly weigh against it:
- An emergency fund. Money in your house isn't easy to get back. You'd have to sell or borrow against your equity, and borrowing may not be available when you need it most.
- Higher-interest debt. Credit cards, personal loans, or car loans charging more than your mortgage rate usually cost you more per dollar than the mortgage does.
- Retirement contributions, especially any employer match you'd otherwise miss.
- Other savings goals you'd need cash for in the next few years.
None of these makes a recast a bad idea. They're reasons to make sure the lump sum is money you won't need to get back out.
Recast, or just prepay?
If you've decided to put the money toward your mortgage, the recast is a separate choice. You can make the same lump-sum payment and not recast. Your payment stays the same and the loan ends sooner.
With the $50,000 example above:
| Recast | Prepay, no recast | |
|---|---|---|
| Monthly payment | $1,770 | $2,098 |
| Interest saved | About $56,200 | About $165,800 |
| Payoff | Same date as now | 8 years, 6 months early |
| Fee | $250 | None |
Prepaying without recasting saves far more interest, because you keep putting the bigger payment toward a smaller balance. Recasting gives up some of that savings in exchange for a lower required payment, and you can still pay extra any month you choose. More on this in recasting vs. extra payments.
When a recast tends to make sense
- Your cash flow is tight and a lower required payment would make your budget safer, for example before a planned drop in income or a new expense like childcare.
- You've just bought a new home and sold the old one, and want to bring the payment down to what it would have been with a bigger down payment. See recasting after buying a new home.
- You like your rate and don't want to refinance into a higher one.
- You're paying PMI and the lump sum gets you close to 80% of your home's original value. You may be able to drop PMI at the same time. See recasting and PMI removal.
- You want flexibility. A lower minimum payment, with the option to pay more when it suits you.
When it may not be worth it
- The lump sum is small and the fee is high, so the break-even stretches past a year or two.
- You plan to sell soon. The lower payment only helps for as long as you hold the loan. The principal you paid comes back to you in the sale proceeds, but the fee doesn't.
- Your main goal is to be mortgage-free sooner. Prepaying without recasting gets you there faster.
- Your rate is very low and you'd rather keep the cash available.
- The money is your safety net. A HELOC isn't a reliable substitute; see recast vs. HELOC.
A quick checklist
- Is my loan eligible, and what are the fee and minimum? (Ask your servicer. Here's how to request a recast.)
- Does the fee break even in a reasonable time for how long I'll keep this loan?
- Will I still have enough cash for emergencies after the lump sum?
- Do I have debt that costs more than my mortgage rate?
- Do I want a lower payment, or an earlier payoff?
Frequently asked questions
Does a recast save money?
Yes. Paying down principal reduces the total interest you'll pay. In the example above, a $50,000 recast saves about $56,000 in interest after the fee. Prepaying the same amount without recasting saves more.
What's the smallest lump sum worth recasting?
That depends on your servicer's minimum and fee. A useful rule of thumb is to check that the fee breaks even well within the time you expect to keep the loan.
Is recasting better than refinancing?
They solve different problems. A recast keeps your rate and term; a refinance replaces them. See recast vs. refinance.
More recast guides
- How to Request a Mortgage Recast
- Recasting After Buying a New Home
- Recasting and PMI Removal
- Recasting With a Windfall
- Mortgage Recast vs. Biweekly Payments
- Mortgage Recast vs. HELOC
- Recasting ARM and Jumbo Loans
- Mortgage Recast vs. Refinance
- Recasting vs. Extra Mortgage Payments
- Mortgage Recast Glossary