Recasting a Mortgage Is the Option Nobody Mentions

What a recast actually does to the schedule

Three things define an amortising loan: the balance, the rate and the number of payments left. The payment is not a fourth input; it is the output, and our article on the annuity formula derives it. A recast changes exactly one of the three — it reduces the balance — and then recomputes the output. The rate stays where it was, which matters enormously when the rate you have is better than the rate on offer. The maturity date stays where it was, which is what distinguishes a recast from every kind of refinancing.

Because the rate and the remaining term are unchanged, the arithmetic has an elegant property: the payment falls in exact proportion to the principal you paid off. Our lump sum of $60,000 is 16.02 percent of the $374,443.91 balance, and the payment falls by 16.02 percent, from $2,528.27 to $2,123.15. The interest saving is proportional too: $20,000 would have saved $20,512.43, $60,000 saves $61,537.29 and $100,000 saves $102,562.15, all of them a shade over 1.0256 times the lump sum. If you know the multiplier for your own loan you can price any lump sum in your head.

Why keeping the payment saves nearly three times as much

Both options start from the same $314,443.91 at the same 6.5 percent. The difference is what you do with the room the lump sum created. Recasting spends that room on a smaller payment: the loan still runs 300 months, and every one of those months carries interest on a balance that is falling no faster than before. Keeping the payment spends the room on time instead: the same $2,528.27 now covers more principal each month, the balance falls faster, and the loan clears in 207.3 months. Interest is a charge per unit of time on a balance, so removing 92.7 months of it removes far more than lowering the charge while leaving the time intact.

The price of the recast, stated honestly, is $112,821.95 — the extra interest it pays compared with keeping the payment. What that money buys is $405.12 a month for 300 months, which is $121,537.29 of cash flow released into your hands earlier. Written that way it is not obviously a bad trade; it is a liquidity trade, and whether it is worth $112,821.95 depends entirely on what the freed cash flow is for. If it is going into a savings account earning less than 6.5 percent, the trade is poor. If it is the difference between meeting your obligations and not, the trade is excellent and the interest is the price of not defaulting.

Against a refinance, the answer depends on the maturity

Refinancing changes two things at once, and only one of them is usually discussed. It changes the rate — here from 6.5 to 6.0 percent, a genuine improvement — and it resets the number of payments, which is where the damage hides. Refinance the $314,443.91 over a fresh twenty-five years, so the maturity is unchanged, and you get a payment of $2,066.49 and save $78,535.87: better than the recast on both counts. Refinance the same amount over a fresh thirty years and the payment falls further, to $1,922.96, while the saving collapses to $6,217.79. Same rate, same principal, same fees. Five extra years of interest ate 92 percent of the benefit.

So the honest ranking is not a single order. Against the two options that keep the maturity — recast and same-maturity refinance — and against keeping the payment, the recast saves the least. Against a refinance that resets to thirty years, the recast saves ten times more. The variable that decides it is the one that is almost never on the comparison sheet: how many months of interest are you agreeing to pay. Whenever someone shows you a lower monthly payment, the first question is over how long, and the second is what it costs in total.

The fee, and why lenders offer it at all

A recast costs a servicing fee — commonly a few hundred, an order of magnitude below the several thousand a refinance costs in origination and closing charges. On our case a $300 fee is 0.5 percent of the lump sum, against 2 percent of the new balance, or $6,288.88, assumed for the refinance. There is no new application, no credit pull, no appraisal and no new title work, which is the whole reason the fee is small: the loan is not being replaced, only recalculated. Fannie Mae's servicing rules describe exactly this — a re-amortisation of the current unpaid balance at the existing rate over the remaining term, after a substantial principal curtailment, documented on a standard agreement form.

Lenders offer it because it costs them almost nothing and prevents something expensive. A borrower whose payment has become unaffordable is a borrower who may refinance away — taking the loan and its interest stream with them — or worse, fall behind. A recast retains the loan at its original rate for its original term while removing the pressure, and the servicer keeps a performing asset. Notice that the incentive runs in the lender's favour when the current rate is higher than yours: they would much rather re-amortise a loan at 6.5 percent than lose it to a competitor at 6.0. That is not a reason to distrust the offer, but it is a reason to check whether refinancing at the same maturity would have served you better.

When it is the right answer

Two situations make the recast clearly correct, and they share a shape: a windfall arriving at the same time as a cash-flow problem. The first is the classic bridge. You bought before selling, so you are carrying two housing payments; when the old property completes, a large sum arrives and the obligation you want reduced is the one on the new loan. A recast converts the proceeds directly into a lower monthly payment on a loan you have already been approved for, in weeks and for a few hundred, with no second underwriting at a moment when your file — carrying two mortgages — would look poor.

The second is a change in income with the loan already in place: retirement, a move to part-time work, a household going from two incomes to one. Here the payment is the problem and re-underwriting is exactly what you cannot survive, because the new income would not support the loan you already have. A recast asks nothing about your income. It only asks for the money. That is the feature, and it is why the option belongs in the conversation even though its interest saving is the smallest.

Not every loan permits it. Many government-backed programmes do not, adjustable-rate loans often do not, and servicers frequently set a minimum lump sum and a minimum payment reduction before they will process one. In continental Europe the product usually does not exist under that name at all, because the equivalent is built into the right of early repayment: make a partial prepayment and the contract typically lets you choose between reducing the instalment and shortening the term, which are precisely our first two options. What differs there is not the mechanism but the toll — French law caps the early repayment indemnity at six months' interest on the sum repaid or 3 percent of the outstanding capital, whichever is lower, and German law provides for a prepayment compensation within statutory limits. Ask your lender three questions: is a recast permitted, what is the minimum, and what does a partial prepayment cost me first.

Frequently asked questions

Does a recast change my interest rate?

No, and that is the point of it. The contract is not replaced, so the rate, the index if it has one, the maturity date and every other term carry on unchanged. Only the principal and therefore the payment move. That makes it strictly better than refinancing when your existing rate is below the market — you keep a rate you could not get today — and strictly worse when the market has fallen well below your rate, because you are declining to capture the improvement. The threshold is not a fixed number of points; run both and compare the total, not the payment.

Can I recast more than once?

Sometimes, and the servicer decides. Where it is permitted, each recast carries its own fee and its own minimum lump sum, so a series of small ones is usually uneconomic — the fee is fixed while the benefit scales with the amount. The alternative that costs nothing is to make extra principal payments as they arise without asking for a re-amortisation: the schedule shortens automatically, you capture the larger interest saving, and you can request a single recast later if your circumstances change. That sequence gives you the best of both, at the price of not having the lower payment in the meantime.

Is a recast the same as a loan modification?

No, and the difference matters for how it is treated. A recast is a voluntary re-amortisation you pay for with your own money while the loan is performing; the terms other than principal are untouched, and the servicer processes it as an administrative act. A modification is a change to the contract itself — rate, term, sometimes principal — usually granted because the borrower is in or near difficulty, and it may be reported differently and carry consequences a recast does not. If a servicer describes what you are asking for as a modification, ask why, and ask what will be reported.

What if I want the lower payment but also the interest saving?

You can have both, in sequence, and the trick is that a recast lowers the required payment without preventing you from paying more. Recast to bring the obligation down to $2,123.15, then pay whatever you can above it in the months when you can. In the months you pay the old $2,528.27 you get exactly the same principal reduction as if you had never recast; in the months you cannot, you owe only $2,123.15. The lower floor is the insurance and the voluntary extra is the saving, and nothing except the fee is lost by having both.

Should the lump sum go into the mortgage at all?

That is a separate decision and it should be taken first. Paying down a loan earns you its rate, risk-free and tax position aside — 6.5 percent here — but converts liquid money into equity you can only reach by selling or by borrowing again within a loan-to-value cap, as our article on home equity sets out. Before deploying $60,000 into a mortgage, check that you keep enough cash for the emergencies that would otherwise be funded at credit-card rates, and clear any other debt priced above the mortgage rate. Only what survives those two tests belongs in this comparison at all.