When does refinancing pay off? The break-even point explained

A lower rate sounds like free money, but a refinance is a new loan, with new fees paid up front. It only pays off if you keep the new loan long enough for the savings to cover those costs. That moment is the break-even point, and how you measure it matters more than most refinance offers admit.

The quick rule

The usual shortcut divides the refinance costs by the monthly savings. Pay $6,000 in fees to save $250 a month and you break even after 24 months. Keep the loan longer and you are ahead; sell or refinance again sooner and you have lost money.

The shortcut is a good first filter. Its weakness is that it only looks at the payment, and a lower payment does not always mean a cheaper loan.

The example

Suppose you owe $300,000 at 7%, with 27 years left: a payment of about $2,063 a month. A lender offers 6% on a new 30-year loan, with $6,000 of closing costs. The new payment is about $1,799, saving about $265 a month. The quick rule says you break even after about 23 months.

But the new loan also stretches your remaining 27 years back to 30. Part of the lower payment comes from repaying the balance more slowly, not from the lower rate. Count the balance still owed on each loan as well as the payments, and the true break-even comes after 25 months. Keep the loan seven years and you end up about $13,500 ahead.

Keeping your end date

Now take the same 6% rate on a 27-year term, so the loan still ends when it would have. The payment is about $1,872, saving only about $191 a month, and the quick rule says 32 months. Yet counting the balance, this version breaks even after 24 months, sooner than the 30-year one, and leaves you about $14,900 ahead after seven years.

This is the main trap of the payment shortcut: it flatters a loan that restarts the clock and undersells one that keeps your end date. The balance you still owe is real money, and a complete comparison has to include it.

When the saving is too small

Try a smaller drop, from 7% to 6.5%, on a new 30-year loan. The payment falls by about $167 a month, and the quick rule says three years. After seven years you would be ahead by only about $2,900. And if you kept the new loan to the end, it would cost more: about $383,000 of interest over 30 years, against about $369,000 still due on the current loan over 27. A small rate drop plus a reset term can lower the payment and still cost more in total.

What to check before refinancing

How long you will keep the loan. This decides everything. If you may move within the break-even period, the fees are a loss.

The full cost, not only the rate. Lender, appraisal and title fees often add up to a few percent of the loan. Costs rolled into the new balance avoid a cash payment but add interest.

The term. Compare a new loan that ends when your current one would, not only a fresh 30 years. You can also take the longer term and keep paying the old amount: the extra goes to principal.

What rates are doing. Weekly survey rates give a sense of whether an offer is competitive, but your own rate depends on your credit, loan size and equity.

Run your own numbers in the refinance calculator, which counts the balance still owed as well as payments, and see how each loan repays month by month in the amortization calculator. For why a long term costs so much more, read how amortization works.