Personal Finance · 7 min read · 2026-04-21
The 9-signal refinance break-even test.
A 100-basis-point rate drop is not, by itself, a reason to refinance. The decision is a multi-variable break-even, and most retail miscalculates the inputs.
Refinancing the wrong year wastes the savings on closing costs.
Closing costs on a typical U.S. residential refinance run $6,000 to $12,000 depending on state, loan size, and lender. The refi pays off only when monthly savings recover those costs over the holder's actual remaining time in the home. Most retail underestimates the closing cost and overestimates the holding period.
The nine indicators
The nine inputs of every refinance break-even.
Each is verifiable from the loan estimate, the existing note, and the holder's life situation. The composite produces a single break-even date.
All-in closing costs as percent of loan
Threshold: < 2.0%
Closing costs above 2 percent of the loan size make break-even longer. The Loan Estimate (Form RESPA-TRID) lists every fee.
Rate reduction of 75+ bps
Threshold: > 0.75 pp
Below 75 basis points of rate reduction, the savings rarely justify the closing cost on holding periods under five years.
Expected remaining time in the home > break-even period
Threshold: T_home > T_be
If the break-even is 36 months but the holder plans to move in 24, the refi loses money.
Loan term staying or shortening, not extending
Pattern: refi to 20y or 15y
Resetting a 30-year mortgage to a new 30-year resets the amortization clock. Refis to 20- or 15-year terms preserve the principal-paydown trajectory.
Property tax and insurance escrow recapture handled
Pattern: escrow refund timing
Refinancing generates an escrow refund that takes 4–8 weeks. Cash-flow planning requires this lag.
Mortgage interest deduction value calculated correctly
Method: marginal × interest paid
Lower interest on the new loan reduces the mortgage interest deduction. The after-tax savings is gross savings × (1 - marginal rate).
Cash-out portion (if any) earmarked for productive use
Use: investment, debt consolidation
Cash-out refis to fund consumption are wealth-destroying. Productive use (debt consolidation, home improvement, investment) is where cash-out wins.
Loan-to-value ratio supporting best pricing
Threshold: LTV < 80%
LTVs above 80 percent require PMI or a rate premium. Refinancing to capture appraisal-based equity gains can drop LTV under the threshold.
Rate lock period fits closing timeline
Threshold: lock > 30 days
Rate locks expiring before closing force re-locking at potentially worse rates. Lock timing should be aligned with realistic close dates plus a safety margin.
The break-even formula, properly stated
Break-even on a refinance is the number of months it takes for the monthly payment savings to recover the closing costs. The formula is straightforward: closing costs divided by monthly savings equals break-even months. A $7,500 closing cost recovered by $250 of monthly savings is 30 months — a refi that pays off if the holder stays at least 30 months and is wasted if the holder leaves earlier.
The trap is that 'monthly savings' must be computed correctly. Many borrowers simply subtract the new payment from the old, without adjusting for the change in escrow, the lost mortgage-interest deduction, the foregone investment return on the closing-cost cash, and the change in amortization schedule. The simple subtraction overstates savings; the corrected calculation is meaningfully more conservative.
The 75-basis-point heuristic and where it breaks
Conventional wisdom says a 75-basis-point rate reduction is the threshold above which refinancing is worth considering. This heuristic is roughly correct for a $400,000 loan, $8,000 closing cost, 30 percent marginal tax rate, and 10-year holding period. It breaks for smaller loans (where closing costs are larger as a percent of balance), shorter holding periods, and for borrowers using the standard deduction (where the mortgage interest deduction has zero marginal value).
The discipline is to compute the actual break-even rather than rely on the heuristic. Free calculators are widely available; the inputs require attention rather than computation.
Restarting amortization is the hidden cost
A 30-year mortgage in year 8 has 22 years of remaining principal payments and is making meaningful principal-paydown progress each month. Refinancing into a new 30-year mortgage resets the clock — the new loan is again front-loaded with interest, and the principal paydown over the next 22 years is meaningfully slower than under the old loan.
The fix is to refinance into a 20- or 15-year term. The shorter term preserves (or accelerates) the principal-paydown trajectory and typically prices 25–50 basis points better than the equivalent 30-year. The trade-off is a higher monthly payment, which not all borrowers can absorb.
Cash-out refis — the productive-use test
Cash-out refinancing converts home equity to cash by increasing the loan balance. The economics work only when the cash is deployed at a return higher than the new mortgage rate. Debt consolidation (paying off 18% credit cards with a 6% mortgage) is a clear winner. Home improvements that add appraised value are a possible winner. Funding consumption (vacations, cars, lifestyle) is a clear loser.
The discipline is to require a documented productive use before any cash-out. Most cash-out borrowers under-document the destination of the funds, and the disciplined version of the same loan would have been declined.
When not to refinance
The refi is the wrong move when the holder plans to move in less than the break-even period; when the rate reduction is below 50 basis points and closing costs exceed 1.5 percent of the loan; when the new loan extends the amortization meaningfully; or when the closing cost is being financed into the loan (which obscures the break-even by shifting it from cash to balance).
A useful test: if the math requires assumptions about future rate moves to make the refi work, the refi is too marginal. The decision should make sense at current rates with a conservative holding-period estimate.
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Common questions
Questions.
What's a 'no-cost' refinance?
Lenders offer slightly higher rates in exchange for absorbing closing costs. The rate premium is typically 25–50 basis points. The break-even on a no-cost refi is immediate but the lifetime cost is higher; the trade-off favors short holding periods.
Should I refinance to remove PMI?
Often yes, when home appreciation has dropped LTV below 80 percent. The PMI savings can be 0.50–1.50 percent of the loan annually, which is meaningful even before any rate reduction.
How long do refinances take to close?
Conventional residential refis typically close in 30–45 days. Cash-out and jumbo refis can extend to 60+ days. Plan rate locks accordingly.
Is an ARM refi a good idea?
Sometimes. ARMs make sense when the holder is highly likely to move within the initial fixed period. The rate savings versus a 30-year fixed can be 50–100 basis points, which compounds over the holding period.
Do I need an appraisal for a refi?
Usually yes, but many lenders offer appraisal waivers for low-LTV refis or borrowers with strong credit. The waiver saves $400–700 of closing cost.
Can I refinance with bad credit?
Generally yes, at worse pricing. The rate premium for sub-680 credit is typically 50–150 basis points. The credit-score-rebuild work that improves the score over 6–12 months often pays for itself in refi savings.
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