A mortgage refinance is rarely free. Even a 'no-cost' refi bakes the closing costs into a higher rate. The break-even month is the single number that tells you whether the swap is actually worth doing: it is the month in which the cumulative payment savings finally cover the cash you spent at closing. Before that month, you are losing money on the deal. After that month, every dollar you save is real.
The math is simple. Take your current monthly principal-and-interest payment, subtract the new monthly principal-and-interest payment, and divide the closing costs by that monthly saving. The answer is the number of months you need to keep the new loan to come out ahead. If your closing costs are 6,000 dollars and the new loan saves you 250 dollars a month, you break even in month 24. If you sell or refinance again before month 24, you lost money. After month 24, the savings are pure.
Suppose your current loan is 280,000 dollars at 7.25 percent with a payment of 1,910 dollars. A refinance to 6.25 percent on the same balance with closing costs of 5,800 dollars drops the payment to 1,724 dollars, a monthly saving of 186 dollars. Dividing 5,800 by 186 gives a break-even of 31 months, or just over two and a half years. If you expect to keep the house at least five years, the refi pays off. If you plan to sell in 18 months because of a job relocation, the refi loses you about 2,200 dollars.
Does this tool include private mortgage insurance changes?
No. Many users refinance specifically to drop PMI when their loan-to-value crosses 80 percent. If your refi eliminates PMI, add that monthly saving to the payment difference for a more accurate break-even.
What rate of return should I assume on the closing costs?
This tool intentionally ignores opportunity cost to keep the answer simple and honest. If you want to be conservative, add about one month to the break-even for every 10,000 dollars of closing costs.
Why does the break-even seem long when rates only dropped half a point?
Closing costs of 4,000 to 6,000 dollars take 30 to 50 months to recover at small payment savings. Most refis below a 0.75 point rate drop are not worth doing unless you plan to stay in the home for decades.
Should I roll closing costs into the loan instead of paying cash?
Either way the cost shows up. Rolled costs raise your principal and your payment slightly; cash costs raise your out of pocket. The break-even month is roughly the same either way.
Does this work for a cash-out refinance?
Only partially. A cash-out refi pulls equity out of the home, which is a different decision than rate-and-term. Use this tool only on the rate-and-term portion.
This page is for general educational information only. It is not financial, tax, legal, or medical advice. Consult a qualified professional before making decisions based on this tool.