Refinance Calculator

The break-even month is the simplest decision statistic in mortgage refinancing: closing costs divided by the reduction in monthly payment. If a lender charges 5,000 dollars and the payment falls by 334 dollars, the borrower recovers the outlay in the fifteenth month, and every month held beyond that is net gain. Because both inputs are quoted on the Loan Estimate a lender must issue within three business days of application, the ratio can be computed before committing to anything. Typical closing costs run 2 to 5 percent of the loan and decompose into origination or underwriting fees, an appraisal at roughly 300 to 700 dollars, lender's title insurance and a title search at 700 to 900 dollars, credit and flood certification fees, and county recording charges. The ratio has known blind spots. It measures cash-flow recovery, not wealth: if the new term is longer than the term remaining on the old note, the payment can fall while lifetime interest rises, so a favourable break-even and a negative total-cost result can coexist. It also ignores the discount rate on the cash spent, the tax treatment of points, and the fact that a no-closing-cost refinance simply moves the fee into a higher coupon, producing an infinite apparent break-even that is not free. Practitioners therefore pair the ratio with an expected holding period. Because rate declines trigger further refinancing, the relevant horizon is expected loan life rather than expected residence, and a break-even under 24 months is usually treated as clearly favourable, 36 to 48 months as acceptable for a borrower who intends to stay put.

The break-even test entered household finance through consumer education rather than academic theory. As refinancing became common after the rate peaks of the early 1980s, trade guidance condensed the decision into rules of thumb, most famously the 2 percent rule, which held that refinancing paid only if the new rate was at least two percentage points below the old one. That rule was always crude because it ignored balance size, closing costs and holding period; a 2 percentage point drop on a small balance can fail to cover fees, while half a point on a large one can pay back quickly. The cost-divided-by-savings ratio replaced it as the standard consumer heuristic and is the form the Consumer Financial Protection Bureau and Freddie Mac use in their homeowner materials. Formal treatment came later. Because a fixed-rate United States mortgage embeds a free prepayment option, economists modelled refinancing as an option exercise problem in which a borrower should wait for a rate threshold rather than refinance at the first positive break-even. Sumit Agarwal, John Driscoll and David Laibson published a closed-form optimal refinancing rule in the Journal of Money, Credit and Banking in 2013 that sets the threshold using closing costs, the balance, the expected mobility and inflation rates, and rate volatility, and typically yields a differential larger than a naive break-even implies. Disclosure reform made either method usable in practice: the TILA-RESPA Integrated Disclosure rule of October 2015 replaced the good-faith estimate with a standardised Loan Estimate that itemises the closing costs this calculation depends on.