Mortgage Refinance Break-Even Analysis: Closing Costs, Discount Points, and When Refinancing Makes Mathematical Sense

The Core Refinance Equation

Refinancing a mortgage is only financially beneficial if the monthly interest savings offset the upfront closing costs before you move or sell the home. The standard formula to calculate the Break-Even Period in Months is:

\text{Break-Even Horizon (Months)} = \frac{\text{Total Refinance Closing Costs (\$)}}{\text{Net Monthly Payment Reduction (\$)}}

Step-by-Step Worked Scenario

Suppose you have an existing $380,000 loan balance at 7.25% interest with a monthly principal and interest payment of $2,593. Interest rates drop, and a lender offers 6.00% on a new 30-year fixed loan:

• New Monthly Payment: $2,278
• Monthly Savings: $2,593 − $2,278 = $315 / month
• Lender Closing Costs (Title, Appraisal, Origination): $6,300

Break-Even Calculation:

\text{Break-Even} = \frac{\$6,300}{\$315} = 20 \text{ Months (1.67 Years)}

Decision Rule:

• If you plan to remain in the property for longer than 20 months, refinancing is mathematically profitable.
• If you anticipate relocating or selling within 18 months, refinancing produces a net financial loss of several hundred dollars.

Discount Points: Are They Worth Buying?

One discount point equals 1.0% of the loan amount paid upfront to permanently reduce the mortgage interest rate by typically 0.25% (25 basis points).

On a $400,000 mortgage:

• Cost of 1 Point: $4,000
• Rate Drop: From 6.50% ($2,528/mo) to 6.25% ($2,463/mo)
• Monthly Savings: $65/month
• Point Break-Even: $4,000 ÷ $65 = 61.5 Months (5.1 Years)

Buying points rarely makes financial sense unless you are 100% confident you will hold the mortgage for at least 6 to 7 years without selling or refinancing again.

Simulate your custom refinance scenario and amortization curve using our Mortgage Calculator.