If you locked your mortgage in 2023 or early 2024 at rates in the 7-7.5% range, the current sub-6.5% PMMS averages probably look like a refinance opportunity. They might be. They might also not be. Refinance lenders have every incentive to make the decision look obvious — origination fees on a refi work out to thousands of dollars in their pocket. The honest version requires walking through four options, not one.
The worked example
Throughout this page, the math uses a representative scenario: a borrower who took out a $400,000 conventional 30-year fixed mortgage at 7.25% in early 2024. After 24 months of payments, the remaining balance is about $391,967 with 336 months (28 years) remaining. The original P&I payment is $2,728.71/month. Current Freddie Mac PMMS 30-year rate is 6.37%, and refi rates often run 0.1-0.2 points above purchase rates, so an actual refi quote might come in around 6.45-6.55%.
Adjust the numbers below to your loan. The structure of the decision is the same regardless of loan size.
Option 1: Refinance
Replace your existing mortgage with a new one at today's rate. Pay closing costs (typically 2-3% of the loan amount, so $7,800-$11,700 on this loan). Reset the term — usually to a fresh 30-year, sometimes to a 15-year or 20-year if you want to shorten.
The math on this loan at different refi-rate scenarios:
| Refi rate | New P&I | Monthly savings | Break-even ($8K costs) |
|---|---|---|---|
| 6.37% | $2,503 | $225 | 35.5 months (3.0 years) |
| 6.00% | $2,411 | $318 | 25.2 months (2.1 years) |
| 5.50% | $2,289 | $440 | 18.2 months (1.5 years) |
| 5.00% | $2,170 | $559 | 14.3 months (1.2 years) |
The break-even calculation is simple: closing costs divided by monthly savings = how long you need to stay in the home (or keep the loan) for the refi to pay off. If you'll sell or move before break-even, you lose money on the refi. If you'll stay past break-even, you gain.
The rule of thumb that "you need a 1% rate drop to refinance" is roughly correct on this loan — a refi from 7.25% to 6.37% (an 0.88% drop) hits break-even at 3 years. Anything shorter and the refi math breaks down quickly. But "1% drop" is a heuristic, not a rule — what actually matters is the break-even period against your expected hold time.
What refinance also changes
Refinancing isn't just a rate change. It's a new loan, which means:
- The term resets. If you refinance a loan that has 28 years remaining into a new 30-year, you've extended your loan by 2 years. The lower payment looks great, but if you had been planning to pay it off in 28 years, you've just added 2 years of payments. Lifetime interest may not actually drop unless you keep paying the original payment amount.
- You pay closing costs. Typically 2-3% of the loan amount, often rolled into the new loan balance. Rolling costs into the loan reduces upfront cash but means you pay interest on the closing costs for 30 years.
- You may pay PMI again. If your refinance loan-to-value crosses the 80% threshold, you may need to pay PMI even if you'd previously gotten rid of it on the original loan. Worth checking before signing.
- Your credit takes a small hit briefly. The new loan inquiry and the change in your credit profile typically dings FICO by 5-15 points for 6-12 months.
- The escrow account resets. Your existing escrow balance comes back to you as a check after closing; the new lender starts a fresh escrow account that requires 2-3 months of initial deposits at closing.
Option 2: Recast
This option gets less attention than it deserves. A recast is when you make a large lump-sum principal payment, and the lender recalculates your monthly payment at your original rate over your remaining term. The interest rate stays the same. The remaining term stays the same. The monthly payment drops because the principal balance dropped.
On the worked example: if you pay $20,000 lump-sum toward the $391,967 balance, the new balance is $371,967. The lender recasts the payment at the original 7.25% rate over the remaining 336 months. New P&I: $2,589. Monthly savings: $139. Cost: typically a $250 admin fee — no closing costs, no appraisal, no re-qualifying.
Why recast can be the right answer:
- You don't lose your rate. If your existing rate is higher than today's market, you keep the high rate — but you're paying interest on a smaller balance.
- The fee is trivial. $250 vs. $8,000+ in refi closing costs.
- The term doesn't reset. You're still on track to pay off in your original timeline.
- The math is unambiguous. You're trading principal payment today for lower monthly payments going forward. The break-even calculation is simple: lump sum divided by monthly savings = months to recoup.
Where recast falls short: if your existing rate is meaningfully above current market rates (the 7.25% vs. 6.37% gap in our example), refinancing captures lifetime-interest savings that recasting doesn't. Recasting reduces interest by paying down principal at the original rate; refinancing reduces interest by lowering the rate itself. For large rate gaps, refi wins on lifetime math even after closing costs. For small rate gaps (under 0.5 points), recasting often wins because you avoid the closing costs.
Not every lender offers recasting on every loan, and FHA/VA loans typically don't allow it. Check with your servicer before assuming it's available.
Option 3: Extra payments
The free option. Make additional principal payments alongside your regular monthly payment. No fees. No appraisal. No closing costs. Each extra dollar paid toward principal saves you future interest at your existing rate.
On the example: an extra $300/month on the $391,967 / 7.25% / 28-year loan shortens the loan by about 7 years and saves roughly $130,000 in lifetime interest. The math compounds because each extra payment reduces the principal that all subsequent interest is calculated on.
The case for extra payments over refinancing:
- Zero transaction cost. No closing costs, no fees, no paperwork beyond making the payment.
- Reversible. If life circumstances change, stop the extra payments any time. The base loan continues as normal. Compare to a refi, which is a one-way decision.
- Captures interest savings at your existing rate. Each extra dollar to principal saves the rate you locked, not the current market rate. On a 7.25% loan, every extra payment earns a guaranteed 7.25% return (in interest avoided).
The case against extra payments as a substitute for refinancing: extra payments don't lower your monthly payment. If you need or want lower monthly cash outflow, extra payments don't deliver it. They shorten the loan and reduce lifetime interest, but the monthly nut stays the same until the loan is fully paid off.
The Early Payoff calculator models extra-payment scenarios in detail. For an apples-to-apples comparison of monthly extra vs. annual lump vs. biweekly at the same annual dollar amount, the Extra Payment vs. Biweekly calculator shows which strategy saves the most.
Option 4: Do nothing
Sometimes the right answer. If your existing rate is reasonable relative to where rates are likely to be over the medium term, your cash flow is comfortable at the current payment, and you'd use any payment savings on things that don't compound (lifestyle spending, generic savings, etc.), the rational choice may be to leave the loan alone.
Reasons to choose "do nothing" deliberately rather than by default:
- You'll sell or move within 2-3 years. Most refi scenarios don't reach break-even fast enough to pay off if you exit early. Recasting still might if the lump sum is small. Extra payments still make sense for any hold period.
- The rate gap is small (under 0.5 points). The break-even math gets unattractive fast at small rate gaps. A 0.3-point drop on this loan saves about $75/month, which means break-even on $8,000 of closing costs is over 8 years.
- You expect rates to fall further. Refinancing now locks you into today's rates. If you genuinely expect another 0.5+ point drop in the next 12-18 months, waiting may make sense. This requires actual conviction in a rate forecast, not just hope. Forecasts are unreliable.
- You don't have the cash for closing costs. Rolling closing costs into the loan works but adds compounding interest over 30 years. If the rate drop is marginal, rolling costs can erase most of the benefit.
A decision sequence
Five questions, asked in order. Each "yes" or "no" narrows the option set.
- How long will I keep this loan? Under 3 years: probably extra payments or do nothing. 3-7 years: recast or extra payments most likely. 7+ years: refinance is on the table if the rate gap is meaningful.
- How big is the rate gap between my existing rate and current market? Under 0.5 points: refinance math is hard to make work; consider recasting or extra payments. 0.5-1.0 points: refinance is plausible at break-even periods of 3-5 years. Over 1.0 points: refinance is usually the winning option if hold period is long enough.
- Do I need lower monthly payments? Yes: refinancing or recasting deliver lower payments. Extra payments do not. If cash flow is the primary motivation, the options narrow.
- Do I have a lump sum I'd put toward this? Yes: recasting is worth pricing alongside refinancing — sometimes the math wins because you avoid closing costs. No: refinancing or extra payments are the active options.
- Am I confident in my rate forecast? Yes, expecting further drops: waiting may make sense, but read what actually drives mortgage rates first — most consumer rate predictions are wrong. Honest answer is "I don't know," in which case: don't wait for a forecast, decide on the math available today.
What the lender will tell you
If you call a refi lender, the conversation will go a specific way. The lender's job is to close refi loans; their financial interest is aligned with you choosing option 1. Most loan officers are honest about that — they may even mention recasting if you ask — but the default pitch will skip the alternatives.
Things to ask explicitly:
- What are the total closing costs, all-in? Get the dollar number, not just the rate. Closing costs vary dramatically across lenders.
- What's the break-even period on my loan? Make the lender do this math out loud. If they evade or give a generic answer, they're not the lender you want.
- Does my current loan allow recasting? This is a question for your servicer, not the refi lender. Most refi lenders won't mention recasting because it doesn't make them money.
- What happens to my PMI? If the refi LTV crosses 80%, you may pay PMI again. The lender should disclose this; verify it.
- What's the rate without rolling closing costs into the loan? Lenders sometimes quote a lower rate by absorbing some costs and raising the principal. Get both options priced separately.
The flagship lender guide covers refinance shopping in more depth. The same Loan Estimate comparison principles apply — collect 3-4 LEs, compare apples-to-apples, pick the winner.
Where to run your specific numbers
The Refinance vs. Keep calculator takes your current loan parameters and a refi quote, and returns the exact break-even and lifetime-interest comparison. The Early Payoff calculator models extra-payment scenarios. If the refi's underlying purpose is cash extraction rather than rate reduction, the HELOC vs. Cash-Out Refi calculator compares the two paths directly — borrowers with a favorable existing rate usually find HELOC wins. For the deeper context on whether to refinance now or wait, what actually drives mortgage rates covers the structural dynamics that determine whether rates are likely to keep moving.
The honest meta-rule: there's no universally correct answer. Refinance, recast, extra payments, do nothing — each is the right choice for some borrowers in some situations. The math determines which one is right for you. Don't take the lender's word for it; don't take the financial press's word for it; run the calculation on your specific numbers and pick the option whose math you can verify.