Every refinance offer in your mailbox claims to save you money. Most of them don’t. The ones that do can usually be evaluated in under a minute using one number — your break-even point — and two follow-up questions. Here is the test, exactly as I run it on the first phone call.
The One Ratio: Break-Even Months.
The math is this simple:
Break-Even Months = Closing Costs ÷ Monthly Savings
If your refinance has $6,000 in closing costs and lowers your payment by $250 a month, your break-even is 24 months. That means it takes you two years of lower payments to recoup what you paid to get there. Beyond month 25, you’re ahead. Before month 25, you’re behind.
That is the entire frame. Everything else is detail.
The Two Follow-Up Questions.
1. How Long Will You Hold The Loan?
Not the house — the loan. If you’re likely to refinance again, sell the property, or pay it off in any way before your break-even point, the refinance loses money. Period.
Most homeowners overestimate how long they’ll keep a mortgage. The average mortgage in America survives about 7 years before refinance, payoff, or sale. So if your break-even is 18 months, you almost certainly come out ahead. If it’s 60 months, you’re betting on continuity that statistically doesn’t happen.
2. What Are You Giving Up On Term?
This is the trap. Refinancing from a 30-year loan with 25 years remaining into a brand-new 30-year loan resets your clock. Your monthly payment goes down — but you’ve added 5 years of payments at the back end. The “savings” you’re celebrating monthly are partly an illusion of stretching the term.
The honest math compares total cost over the same horizon, not monthly payment alone. Sometimes the right move is a shorter-term refi at a higher monthly that lowers lifetime cost dramatically.
The Four Recommendation Buckets.
When we run the numbers on a refi file, every result lands in one of four buckets. We use the same labels we built into our refinance calculator:
- Run It — Break-even is 24 months or less, and you plan to keep the loan longer. Do it.
- Probably — Break-even between 24 and 48 months. Worth doing if your hold horizon is long.
- Borderline — Break-even between 48 and 60 months. The math is close. Other factors (eliminating PMI, dropping a HELOC, changing structure) might tip it.
- Not Yet — Break-even over 60 months, or savings are flat. Wait. The market will move.
“We tell more borrowers ‘Not Yet’ than ‘Run It.’ That’s the job.”
Two Common Mistakes Worth Avoiding.
Mistake 1: Rolling Closing Costs Into The Loan And Ignoring Them.
“No closing costs!” usually means closing costs were added to your loan balance. You’re still paying for them — with interest, over the term of the loan. The break-even math doesn’t change. The cost just gets hidden inside the principal.
Always run break-even on actual costs, regardless of whether they’re paid out of pocket or rolled in.
Mistake 2: Comparing Payment To Payment Without Adjusting For Term.
If your current loan has 22 years left and you refinance into a 30-year, your new payment will look better even if your rate didn’t improve much. That’s not savings. That’s amortization extension. Compare lifetime cost. Compare paydown velocity. Compare payment-to-payment at the same remaining term.
When The Refi Isn’t About Rate.
Three legitimate reasons to refinance even when the rate math is marginal:
- Dropping mortgage insurance — Refinancing out of FHA MIP can save more than the rate change alone, because MIP is layered on top of rate.
- Consolidating a HELOC or second mortgage — A first-lien rate is almost always lower than a HELOC variable rate. The savings come from the structure, not the rate spread.
- Removing a borrower — Divorce, death, co-signer release. The refinance accomplishes a legal change that has nothing to do with savings.
The Honest Answer.
Refinances are oversold because lenders are paid every time you originate. We get paid the same way. The only thing that keeps the industry honest is the broker’s willingness to say “not yet” when the math doesn’t pencil.
The 30-second test above is the version I’d teach my own family. Run it on every refi offer that hits your inbox. The ones that survive the test are worth a phone call. The rest aren’t.
— Jason Stern is the founder of Hero Mortgage Group, a firefighter-owned brokerage licensed in 12 states. NMLS #1569493.