When to Refinance Your Mortgage (and When Not To)

Every refinance has a cost. Closing costs typically run 2 to 3 percent of the loan amount. On a $500,000 loan, that's $10,000 to $15,000 out the door before you save a dollar on interest.

The break-even math is simple: divide closing costs by the monthly savings the new rate produces. That gives you how many months until the refi pays for itself. Compare that to how long you plan to stay in the home.

This one calculation eliminates most of the complexity. You don't need a spreadsheet with a hundred inputs. You need a realistic estimate of how long you'll stay and an honest look at the closing costs.

The bottom line

Break-even is the headline metric. If the months-to-break-even exceeds how long you'll stay, the refinance isn't worth it at any rate.

There's no universal threshold, but in today's rate environment a common benchmark is a drop of at least 0.5 to 0.75 percentage points. Smaller than that and closing costs tend to erode the benefit before you hit break-even.

The older rule of thumb was a full percentage point or more. That worked when closing costs were proportionally higher and borrowers stayed in homes longer. The modern threshold is lower because lenders compete harder on refis and homeowners move more often.

The bottom line

A half to three-quarters of a point is the modern floor. Anything smaller, and you're usually paying closing costs to save nothing.

One common refinance pitfall: rolling a loan with 22 years left into a fresh 30-year mortgage. The monthly payment drops. The total interest paid over the life of the loan goes up, often substantially.

A reasonable compromise: refinance into a shorter term if the monthly payment still fits your budget. A 15-year or 20-year refinance usually comes with a lower rate than a 30-year and locks in a payoff date.

The bottom line

A lower rate on a longer term is not automatically a win. Look at total interest paid, not just the monthly number.

A cash-out refinance replaces your mortgage with a larger loan and hands you the difference in cash. It has legitimate uses and expensive ones.

• Reasonable uses: value-adding home improvements, consolidating high-rate debt when the new blended rate is meaningfully lower.
• Dangerous uses: vacations, cars, lifestyle spending, or anything that converts equity into consumption.

The bottom line

Equity isn't spending money. Pulling it out adds to your mortgage balance, so the common framing is to reserve it for uses that grow the asset or pay off something more expensive.

Even when the headline rate looks appealing, several situations tilt the math against refinancing. The biggest is timing relative to payoff.

Other cases where the math usually doesn't work:

• You're planning to move within the break-even window. The savings don't compound in time.
• The rate drop is below the modern benchmark, and there's no no-cost option that makes the closing costs disappear.
• Your credit score dropped since you originated. You may not actually get the headline rate.

The bottom line

A refinance is a tool, not a reflex. When the break-even math or the term arithmetic doesn't work, keeping your existing mortgage is the right answer.